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VOLUME I: Fundamentals & Ingredients
Baking Science & Technology
Volume I: Fundam
entals & Ingredients • E.J. Pyler and L.A. Gorton • Fourth Edition
FOURTH EDITION
BAKINGScience & Technology
E.J. PYLERAND L.A. GORTON
SOSLAND PUBLISHING COMPANY
ii /
Copyright © 2008 by Sosland Publishing Company. All rights reserved.
Library of Congress Control Number: 2008934285
ISBN 978-0-9820239-0-7 Baking Science and Technology, Volume 1
ISBN 978-0-9820239-2-1 Baking Science and Technology, 2 Volume Set
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Baking Science & Technology / iii
Foreword
“Baking Science & Technology, 3rd edition” stayed in print for nearly
20 years, but as the industry approached the 2007 International Baking Industry
Exposition, it became clear that a new edition was needed. Much had happened,
especially on the nutrition side as well as with process automation, and the industry
now encompassed many new aspects not covered in the text. The 4th edition was
announced at that international trade show, and this book is the first of two volumes
comprising the new version.
“Baking Science & Technology,” was first published in 1952, then again
in 1972 and 1988. That this book stood the test of time and continues to be used
as a textbook by the industry’s leading baking schools and as a daily reference
for thousands of bakers worldwide is testament to its original writer’s insight and
writing ability.
For the 4th edition, Sosland Publishing approached Laurie Gorton,
executive editor of Baking & Snack. She has nearly 35 years experience covering
the technical, scientific and business aspects of the grain-based foods industry.
The grain-based foods industry and baking in particular face as many, if
not more, challenges than 20 years ago. Today’s issues involve nutritional content,
food safety and the demands of the health-and-wellness shopper. But every era
brings its own concerns to the table, quite literally.
We intend “Baking Science & Technology” to move into the future through
this new edition and, later, digital formats. As developments occur, the book will be
updated using emerging electronic technologies. We encourage readers to comment
on this edition and its contents and to recommend topics and changes for future
inclusion.
Mark Sabo
President, Sosland Publishing Co.
August 2008
Baking Science & Technology / vii
Table of ContentsForeword ................................................................................................................ ii
Chapter 1: Basic Food Science ........................................................................... 1Carbohydrates ........................................................................................................ 2
Sources of carbohydrates used in baking ...................................................... 2
Carbohydrate synthesis ................................................................................... 2
Simple vs. complex......................................................................................... 3
Physical and chemical differentiation ............................................................. 4
Monosaccharides ............................................................................................ 4
Sugar: Disaccharides and trisaccharides......................................................... 5
Starch .............................................................................................................. 7
Dextrins ........................................................................................................ 11
Gelatinization of starches ............................................................................. 12
Retrogradation of starch ............................................................................... 14
Acrylamide formation .................................................................................. 15
Glycemic index vs. glycemic response ......................................................... 16
Pentosans ............................................................................................................ 17
Sources of pentosans in baking .................................................................... 17
Structure ....................................................................................................... 18
Physical and chemical differentiation ........................................................... 18
Functions and effects during baking ............................................................. 18
Fiber ..................................................................................................................... 20
Sources of fi ber ............................................................................................. 21
Defi nition of dietary fi ber ............................................................................. 21
Structure ....................................................................................................... 26
Properties of fi ber in food ............................................................................. 27
Probiotics, prebiotics and synbiotics ............................................................ 27
Proteins and enzymes .......................................................................................... 28
Proteins ......................................................................................................... 29
Sources of proteins ....................................................................................... 30
Amino acids .................................................................................................. 31
Classifi cation of proteins .............................................................................. 34
Structure of proteins ..................................................................................... 39
Properties of proteins .................................................................................... 41
Proteins of wheat .......................................................................................... 43
Enzymes ....................................................................................................... 47
Sources of enzymes ...................................................................................... 47
Classifi cation and nomenclature of enzymes ............................................... 49
Lock-and-key, induced fi t of enzymes .......................................................... 51
viii / Table of Contents
Properties of enzymes ................................................................................... 51
Lipids ................................................................................................................... 55
Source of lipids ............................................................................................. 55
Nomenclature ............................................................................................... 56
Chemical composition .................................................................................. 57
Fatty acids ..................................................................................................... 57
Fatty acid naming protocols ......................................................................... 58
Saturated vs. unsaturated .............................................................................. 58
Cis vs. trans .................................................................................................. 62
Short- and medium-chain fatty acids ............................................................ 63
Mono-, di- and triglycerides ......................................................................... 63
Sterols and stanols ........................................................................................ 64
Other lipids ................................................................................................... 64
Physical aspects ............................................................................................ 64
Liquid, plastic and solid forms ..................................................................... 64
Melting point ................................................................................................ 65
Crystallinity .................................................................................................. 66
Hydrogenation and interesterifi cation .......................................................... 66
Oxidation ...................................................................................................... 68
Autoxidation mechanism .............................................................................. 68
Antioxidants ................................................................................................. 69
Hydrolysis and polymerization ..................................................................... 70
Physical chemistry ............................................................................................... 71
Acid-base reactions ...................................................................................... 71
Electrolytes ................................................................................................... 71
Titration ........................................................................................................ 72
Active acidity ................................................................................................ 73
The pH concept ............................................................................................. 74
Buffers .......................................................................................................... 75
pH determination .......................................................................................... 76
Role of pH in baking .................................................................................... 77
Buffering action of proteins .......................................................................... 78
pH in chemically leavened product .............................................................. 79
Oxidation and reduction ............................................................................... 80
The redox potential ....................................................................................... 81
Estimation of redox potential ....................................................................... 81
Role of oxidation in baking .......................................................................... 82
Role of pentosans ......................................................................................... 83
Role of thiols and disulfi des ......................................................................... 84
Role of fl our lipids ........................................................................................ 85
Dough physics: colloids and rheology ................................................................. 86
States of matter ............................................................................................. 87
Baking Science & Technology / ix
Molecular forces ........................................................................................... 88
Colloidal systems .......................................................................................... 89
Emulsions ..................................................................................................... 90
Foams............................................................................................................ 92
Colloidal character of dough ........................................................................ 92
Colloidal aspects of fl our particles ............................................................... 93
Starch ............................................................................................................ 94
Dextrins ........................................................................................................ 96
Pentosans ...................................................................................................... 96
Water solubles ............................................................................................... 97
Flour proteins ................................................................................................ 97
Role of polar fl our lipids ............................................................................... 98
Chemical bonds ............................................................................................ 99
Water in dough .............................................................................................. 99
Adsorption vs. absorption ........................................................................... 100
Cell structure in dough ............................................................................... 101
Dough rheology .......................................................................................... 103
Chapter 2: Bakery Ingredients ....................................................................... 113Part A: Major Ingredients .............................................................................. 113Wheat fl our ........................................................................................................ 114
Structure of the wheat kernel ...................................................................... 115
Components of wheat fl our ........................................................................ 119
Flour treatment ........................................................................................... 136
Flour quality ............................................................................................... 141
Flour absorption .......................................................................................... 144
Flour storage ............................................................................................... 145
Flour milling ...................................................................................................... 147
Flour types .................................................................................................. 152
Pastry, cake and cookie fl our ...................................................................... 152
Germ and bran as fl our components and ingredients ................................ 159
Whole-grain fl our ....................................................................................... 160
Non-wheat fl ours ............................................................................................... 165
Rye .............................................................................................................. 165
Soy fl our ..................................................................................................... 170
Masa (nixtamalized corn fl our) .......................................................................... 175
Sweeteners ......................................................................................................... 176
Sucrose ....................................................................................................... 177
Corn syrups and dextrose ........................................................................... 183
Honey.......................................................................................................... 187
Malt and malt syrups .................................................................................. 189
Lactose ........................................................................................................ 191
x / Table of Contents
Sorghum and maple syrups ......................................................................... 191
Role in breadmaking ................................................................................... 192
Role in cakemaking .................................................................................... 195
Role in cookies and crackers ...................................................................... 197
Shortenings ........................................................................................................ 198
Sources and composition ............................................................................ 200
Physical characteristics ............................................................................... 210
Shortening processing ................................................................................ 213
Categories ................................................................................................... 217
Bakery applications .................................................................................... 223
Frying fats ................................................................................................... 227
Recent issues involving bakery shortenings ............................................... 232
Water .................................................................................................................. 236
Chemical nature of water ............................................................................ 236
Sources of water ......................................................................................... 238
pH variability .............................................................................................. 238
Mineral constituents ................................................................................... 239
Water treatment ........................................................................................... 242
Water’s functions in dough and batter ........................................................ 247
Ice as an ingredient ..................................................................................... 253
Chapter 2: Bakery Ingredients Part B: Minor ingredients ............................................................................... 271Leavening ........................................................................................................... 272
Yeast ........................................................................................................... 272
Bacteria ....................................................................................................... 296
Chemical leavening .................................................................................... 303
Air and steam .............................................................................................. 311
Dairy .................................................................................................................. 312
Milk’s composition ..................................................................................... 312
Commercial forms of milk ......................................................................... 316
Cheese ......................................................................................................... 322
Whey products ............................................................................................ 324
Storage stability .......................................................................................... 327
Nonfat dry milk’s functionality .................................................................. 327
Practical aspects of milk products in baking .............................................. 329
Eggs ................................................................................................................... 330
Structure of eggs ......................................................................................... 331
Processing of eggs ...................................................................................... 337
Commercial forms of eggs ......................................................................... 340
Functions in baking .................................................................................... 346
Recent developments .................................................................................. 348
Baking Science & Technology / xi
Starch ................................................................................................................. 349
Wheat starch ............................................................................................... 350
Supplementary starches .............................................................................. 351
Properties and functions ............................................................................. 355
Starch’s role in bread baking ...................................................................... 356
Cake, cookie, cracker and other applications ............................................. 359
Recent developments .................................................................................. 361
Fiber ................................................................................................................... 363
Composition ............................................................................................... 364
Fiber ingredients and their processing ........................................................ 366
Bakery applications .................................................................................... 371
Bulking agents ............................................................................................ 375
Prebiotics and probiotics ............................................................................ 376
Chapter 2: Bakery Ingredients Part C: Micro ingredients ............................................................................... 391Oxidation, reduction, yeast foods and buffers ................................................... 394
Oxidation and reduction ............................................................................. 395
Reducing agents .......................................................................................... 399
Yeast foods and buffers ............................................................................... 401
Enzymes ............................................................................................................. 402
Amylase in dough ....................................................................................... 402
Cereal proteinases ....................................................................................... 403
Malt ............................................................................................................. 404
Exogenous enzymes ................................................................................... 405
Gluten ................................................................................................................ 412
Nature of gluten .......................................................................................... 413
Gliadin ........................................................................................................ 414
Glutenin ...................................................................................................... 415
Glutenin-gliadin ratios ................................................................................ 417
Glutenin interactions during mixing ........................................................... 417
Sulfhydryl and disulfi de groups .................................................................. 418
Protein-lipid interaction .............................................................................. 420
Vital wheat gluten ....................................................................................... 421
Proteins .............................................................................................................. 423
Concentrates and isolates ........................................................................... 424
Allergens ..................................................................................................... 426
Salt .................................................................................................................... 427
Salt sources and processing ........................................................................ 428
Sea salt ....................................................................................................... 428
Forms and grades ........................................................................................ 429
Specifi c applications ................................................................................... 432
xii / Table of Contents
Salt functionality ........................................................................................ 433
Improvers ........................................................................................................... 437
Emulsifi ers and surfactants ......................................................................... 438
Compounds ................................................................................................. 442
Functionality of improvers ......................................................................... 449
Antioxidants and antimicrobials ........................................................................ 452
Antioxidant ingredients .............................................................................. 454
Antimicrobial ingredients ........................................................................... 456
Spoilage organisms ..................................................................................... 459
Gums (hydrocolloids) ........................................................................................ 466
Sources ....................................................................................................... 466
How they work ........................................................................................... 477
Functions in baking .................................................................................... 478
Enrichment and fortifi cation .............................................................................. 480
Mandatory vs. voluntary ............................................................................. 483
Contemporary issues .................................................................................. 483
Technical considerations ............................................................................. 485
Storage and handling .................................................................................. 486
Beyond vitamins and minerals ................................................................... 487
Chapter 2: Bakery Ingredients Part D: Characterizing Ingredients ............................................................... 499Fruits .................................................................................................................. 500
Fresh, canned and frozen fruits .................................................................. 500
Dried and dehydrated fruits ........................................................................ 503
Glacé and candied fruit ............................................................................... 509
Nuts .................................................................................................................... 510
True nuts ..................................................................................................... 511
Seed nuts ..................................................................................................... 514
Flavors................................................................................................................ 519
Natural, artifi cial and mixtures ................................................................... 520
Flavor components...................................................................................... 521
Extract processing ...................................................................................... 521
Vanilla ......................................................................................................... 522
Storing fl avor extracts ................................................................................. 526
Spices ................................................................................................................. 526
Sources ....................................................................................................... 527
Processing ................................................................................................... 533
Colors ................................................................................................................. 534
Color additives vs. colorants....................................................................... 535
Certifi able vs. exempt ................................................................................. 536
Dyes and lakes ............................................................................................ 539
Baking Science & Technology / xiii
Caramel color ............................................................................................. 540
Spice blends ................................................................................................ 541
Reactive colors............................................................................................ 541
Cocoa and chocolate .......................................................................................... 542
Chocolate .................................................................................................... 545
Cocoa powders ........................................................................................... 548
Confectionery coatings ............................................................................... 550
Bloom ......................................................................................................... 551
Fabricated particulates ....................................................................................... 552
Chapter 2: Bakery Ingredients Part E: Ingredient Systems ............................................................................. 557Ingredient components ....................................................................................... 560
Ingredient handling ............................................................................................ 561
Processing .......................................................................................................... 562
Mixing equipment ...................................................................................... 562
Blending methods ....................................................................................... 563
Packaging ........................................................................................................... 565
Chapter 3: Crops and their processing .......................................................... 567(By C.E. Walker and J. Li)
Eight principal cereal grains of commerce ........................................................ 569
Barley.......................................................................................................... 569
Corn (maize) .............................................................................................. 571
The millets .................................................................................................. 574
Oats ............................................................................................................. 576
Rice ............................................................................................................. 577
Rye .............................................................................................................. 578
Sorghum (milo) ........................................................................................... 579
Wheat .......................................................................................................... 581
Minor and pseudocereals and special wheats .................................................... 584
Amaranth .................................................................................................... 584
Buckwheat .................................................................................................. 585
Coix (adley, Job’s tears) .............................................................................. 586
Emmer and spelt ......................................................................................... 587
Kamut ......................................................................................................... 587
Quinoa ........................................................................................................ 588
Teff .............................................................................................................. 589
Triticale ....................................................................................................... 589
Pulses and oilseeds ........................................................................................... 590
Non-grain oils ............................................................................................. 590
Coconut ....................................................................................................... 590
xiv / Table of Contents
Olive .......................................................................................................... 591
Palm ............................................................................................................ 591
Oilseeds ...................................................................................................... 592
Canola (rape) .............................................................................................. 592
Flax ............................................................................................................ 592
Peanut ......................................................................................................... 593
Poppy .......................................................................................................... 593
Saffl ower ..................................................................................................... 594
Sesame ........................................................................................................ 594
Soy .............................................................................................................. 595
Sunfl ower .................................................................................................... 597
Pulses .......................................................................................................... 598
Lentil ........................................................................................................... 598
Lupin ........................................................................................................... 599
Crop improvement ............................................................................................. 600
Chapter 4: Quality Laboratory ...................................................................... 613(By T. Cogswell)
The bake test ...................................................................................................... 614
Physical dough testing ....................................................................................... 615
AlveoConsistograph ................................................................................... 616
Extensograph .............................................................................................. 618
Farinograph ................................................................................................. 619
Mixograph .................................................................................................. 621
Rheograph ................................................................................................... 622
Dough quality controller systems ............................................................... 622
Research Extensometer .............................................................................. 623
Maturograph ............................................................................................... 624
Oven-Rise Recorder ................................................................................... 624
Flourometer method ................................................................................... 625
Dough shock test ........................................................................................ 626
Firmness test ............................................................................................... 626
Physiochemical tests .......................................................................................... 626
Near-infrared refl ectance analysis .............................................................. 627
Flour color .................................................................................................. 628
The slick test ............................................................................................... 629
Colorimeter instruments ............................................................................. 629
Ash determination ...................................................................................... 630
Moisture measurement methods ................................................................. 631
Direct (or chemical) methods ..................................................................... 631
Indirect (or physical) methods .................................................................... 632
Flour moisture determination ..................................................................... 632
Baking Science & Technology / xv
The vacuum oven method ........................................................................... 633
The air oven method ................................................................................... 633
The air oven aluminum plate method ........................................................ 634
Protein determinations ................................................................................ 634
Kjeldahl procedure ..................................................................................... 634
Biuret method ............................................................................................. 636
Crude gluten ............................................................................................... 636
Sedimentation tests ..................................................................................... 637
Acidity determinations ............................................................................... 638
pH determination ........................................................................................ 638
Total titratable acidity (TTA) ...................................................................... 639
Free fatty acid titrations .............................................................................. 639
Iodine value ................................................................................................ 639
Enzymatic activity methods ............................................................................... 640
Diastatic activity of fl our ............................................................................ 640
Amylograph method ................................................................................... 641
Rapid Visco Analyzer method .................................................................... 642
Falling Number method .............................................................................. 642
Proteolytic activity ...................................................................................... 644
Determination of sugar ...................................................................................... 644
Gas production methods .................................................................................... 645
Miscellaneous determinations ........................................................................... 646
Lipid content ............................................................................................... 646
Crude fi ber .................................................................................................. 646
Dietary fi ber ................................................................................................ 647
Bread scoring ..................................................................................................... 647
External characteristics ............................................................................... 648
Internal characteristics ................................................................................ 649
Flavor factors .............................................................................................. 650
Scanning systems ........................................................................................ 651
How to set up a bakery laboratory ..................................................................... 652
Testing of raw materials ............................................................................. 652
Flour ........................................................................................................... 652
Sugar ........................................................................................................... 653
Shortening, fats and oils ............................................................................. 653
Measurements during processing ............................................................... 653
Finished product monitoring ...................................................................... 653
Moisture ...................................................................................................... 653
Weight ......................................................................................................... 653
Dimensions ................................................................................................. 653
Salt and fat content ..................................................................................... 654
Suggested laboratory equipment ............................................................... 654
xvi / Table of Contents
Equipment for general use .......................................................................... 654
Equipment for specifi c tests ........................................................................ 655
Chapter 5: Sanitation and Regulations .......................................................... 661(By R.F. Stier)
Sanitation: A prerequisite to safe food ............................................................... 662
Sanitation, food safety and foodborne illness .................................................... 663
Elements of a good sanitation program ............................................................. 663
Sanitation as a system ................................................................................. 664
Areas your sanitation programs should address ......................................... 665
Regulating Sanitation ......................................................................................... 666
Sanitation regulations ................................................................................. 666
Regulatory inspection ................................................................................. 670
Preparing for inspection ............................................................................. 670
The inspection ............................................................................................ 671
Developing sanitation systems ........................................................................... 675
Sanitation SOPs .......................................................................................... 676
Good manufacturing practices .................................................................... 677
Preventive maintenance .............................................................................. 680
PM programs .............................................................................................. 680
Establishing preventive maintenance programs ......................................... 682
Training and education ...................................................................................... 684
Why educate and train? .............................................................................. 685
Understand your audience .......................................................................... 685
Educational needs ....................................................................................... 688
The fi nal element ........................................................................................ 689
Assuring water quality and safety ...................................................................... 689
Ice ............................................................................................................... 692
Water quality analysis ................................................................................. 693
Water quality and its effects on process operations .................................... 694
Cleaning and sanitizing .............................................................................. 695
Plant water systems .................................................................................... 695
Condition and cleanliness of food contact surfaces ........................................... 696
Constraints in cleaning dry processing operations ..................................... 696
How to clean ............................................................................................... 697
Personal hygiene and employee health .............................................................. 701
Hand washing ............................................................................................. 703
Disease control ........................................................................................... 704
Uniforms and garments .............................................................................. 705
Hair restraints ............................................................................................. 706
Jewelry ........................................................................................................ 706
Personnel facilities ...................................................................................... 707
Baking Science & Technology / xvii
Product protection programs .............................................................................. 707
Sanitary design of equipment ..................................................................... 708
Building design and maintenance ............................................................... 708
Floors .......................................................................................................... 709
Drains ......................................................................................................... 709
Walls ........................................................................................................... 710
Ceilings ....................................................................................................... 710
Lighting ...................................................................................................... 711
Doors .......................................................................................................... 711
Traffi c ......................................................................................................... 712
Warehouse design ....................................................................................... 712
Grounds ...................................................................................................... 713
Glass and brittle plastic .............................................................................. 714
Allergen control .......................................................................................... 714
Vendor certifi cation .................................................................................... 715
Receiving and storage ................................................................................. 715
Control in batching and blending ............................................................... 715
Production control and scheduling ............................................................. 715
Control of rework ....................................................................................... 716
Tracking and traceability ............................................................................ 716
Cleaning ...................................................................................................... 716
Education .................................................................................................... 716
Chemical handling and control .......................................................................... 717
MSDS sheets .............................................................................................. 717
Chemicals ................................................................................................... 718
Lubricants ................................................................................................... 718
Pest management ............................................................................................... 719
Premises for program building ................................................................... 719
Pest exclusion ............................................................................................. 720
Monitoring .................................................................................................. 721
Chemicals for pest control .......................................................................... 721
Documenting the program .......................................................................... 723
Verifi cation and recordkeeping .......................................................................... 724
Forms .......................................................................................................... 725
Proper recordkeeping .................................................................................. 725
Appendix: Molecular Drawings ..................................................................... 729
Index: Volume I ................................................................................................ 733
Baking Science & Technology / 1
The basic components of baked foods number in the thousands, even millions. Plants, animals and mineral sources provide the raw materials for baking’s ingredients. Entities such as bakers yeast and bacteria contribute their lives and by-products to baked foods, while inert minerals provide nutritive and functional attributes. At their most basic, the plant and animal compounds are classifi ed as carbohydrates, proteins and lipids.
An understanding of the basic food science aspects of carbohydrates, proteins and lipids will help bakers and other practitioners of the baker’s art in their work to develop products and manage the processing of baked foods. The ability to identify such compounds and recognize their differences goes a long way when solving formulating and production problems.
CHAPTER 1
Basic Food Science
INTRODUCTION
A working knowledge
of the science
of carbohydrates,
proteins, lipids and
fi bers will help
any practitioner
of the baker’s art.
Baking Science & Technology / 1
2 / BASIC FOOD SCIENCE
1.A. Carbohydrates
1.A.1. Sources
Of all the compounds composing baked foods, carbohydrates predominate by sheer quantity, typically accounting for 67% of wheat fl our. Qualities that consumers associate with freshness such as keeping quality, crust and crumb texture, along with fi rmness, result from the condition of the carbohydrates in the product.
In nature, plants store much of the energy supply for their seeds in the form of carbohydrates and also warehouse these compounds in their stems and roots. Carbohydrates make up the bulk of the white, starchy material found in the interior content of seeds and roots.
Typical sources for the carbohydrates in baked foods include wheat kernels, of course, but also corn and other cereal grains and legumes, along with sugar cane and sugar beets. When considering complex carbohydrates and fi ber, sources become even more diverse, including tree exudates, seaweed colloids and fruit pectin as well as root and stem materials from a wide variety of plants.
Glucose, the simple sugar that forms the basis of all carbohydrates, is fundamentally important to life. While mammals derive energy from the glucose they consume, plants put it to additional use. They can transform carbohydrates into lipid substances, and when making proteins, plants combine the hydrogen, carbon and oxygen from its glucose stores with the nitrogen, occasionally sulfur and sometimes phosphorus that it gets from the soil in the form of inorganic salts. The results are complex protein molecules.
1.A.1.a. Carbohydrate synthesisHow do plants make glucose? Through the process of photosynthesis, the chlorophyll
in the green leaves of plants, as well as some algae and bacteria, absorbs electromagnetic radiation from sunlight. This is transformed into chemical energy that acts on carbon dioxide (CO
2) and water
(H2O), turning it into glucose (C
6H
12O
6) and oxygen (O
2). The
process can be expressed by the equation:
6 CO2 + 6 H
2O + energy → C
6H
12O
6 + 6 O
2
The energy component of the process is quite complex and involves highly specialized cells, or chloroplasts, within plant leaves. In cyanobacteria and prochlorobacteria, photosynthesis takes place within the folds of single-celled organisms’ membranes.
Known as the Calvin cycle (Figure 1.01) (other names include Calvin-Benson cycle and Carbon Fixation cycle), it resembles the Krebs cycle in its use of the electron-transport molecules adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADP+). During the Calvin cycle, enzyme-mediated reactions split the water to release the oxygen and reduce the carbon dioxide to create carbon-carbon covalent bonds and to accept hydrogen, thus forming carbohydrates. These compounds,
Figure 1.01. During the Calvin cycle, enzyme-mediated reactions split water to release the oxygen and reduce the carbon dioxide to create carbon-carbon covalent bonds and to accept hydrogen, thus forming carbohydrates.
three molecules ofCO2 fixed give a netyeild of one moleculeof glyceraldehyde3-phosphate at a netcost of nine moleculesof ATP and sixmolecules of NADPH
SUGARS, FATTY ACIDS, AMINO ACIDS
one molecule
glyceraldehyde3-phosphate
3C
2
O
O
O
H C
C
C
H H
H
three molecules
1C2OC
five molecules
glyceraldehyde3-phosphate 3C
three molecules
ribulose5-phosphate 5C
three molecules
ribulose5-phosphate 5C
P2
3
3
6
6
six molecules
3C1,3-diphosphoglycerate
six molecules
3C3-phosphoglycerate
six molecules
glyceraldehyde3-phosphate 3C
i
Pi
ADP
ATP
6
6
6
ADP
ATP
NADPH
NADP*
Pi
Part A: Major Ingredients / 113
Bakery Ingredients Part A: Major Ingredients
INTRODUCTION
In practice, bakers tend to group ingredients into three categories based on their level of usage in formulations: major, minor and micro. Major, also termed “bulk,” ingredients make up the majority of the formulation. Flour, for example, constitutes around 55 to 60% (formula weight) or more of bread’s raw materials. Minor ingredients typically range from 5 to 10% (formula weight), and micro ingredients are those added at 5% or less.
CHAPTER 2
High-quality
baked foods
demand use
of high-quality
ingredients.
Part A: Major Ingredients / 113
114 / BAKERY INGREDIENTS
This classifi cation came about when bakeries started installing automated ingredient handling systems. Return on investment came rapidly for capital spent on the silos, scales, sifters and control systems suitable for storing, portioning and dispensing bulk ingredients. The payout for automating the handling of ingredients used at lower rates was not as fast, so installation tended to lag. Manual scaling and hand-add delivery usually characterize the handling of minor and micro ingredients. A good number of large bakeries do automate their ingredient systems through the micro level, but it is far more common to fi nd only the bulk materials dispensed through computerized systems.
For this reason, the discussion of bakery ingredients will follow a major, minor, micro format. Also presented will be coverage of characterizing ingredients, and ingredient systems such as bases, concentrates and mixes.
2.A.1. Wheat fl our
Wheat is the No. 1 cereal in the world in terms of area planted. Corn’s production numbers are higher, and more of the planet Earth’s people eat rice, but wheat remains the premier food cereal grain. The reasons for this preeminence are many. Wheat is well adapted to the soil and climatic conditions that prevail in the large temperate regions across the globe. The wheat plant is high-yielding and relatively easy to cultivate. The mature grain possesses excellent storage stability and exceptional food value. Its yield of suitable fl our upon milling is relatively high, and there is practically no waste since the by-products of milling are used as animal feed.
Table 2.A.01. US Wheat Classes and Principal Uses Class General characteristics Principal usesHard red winter (HRW) High protein, Bread and related products strong gluten, high water absorption Soft red winter (SRW) Low protein, Cakes, cookies, pastries, pie crusts, crackers, biscuits weak gluten, low water absorption Hard red spring (HRS) Very high protein, Bread, bagels, pretzels and related products strong gluten, high water absorption Hard white High protein, Bread and related products Strong gluten, high water absorption, bran lacks pigments Soft white Low protein, Noodles, crackers, wafers and other weak gluten, products in which specs are undesirable low water absorption, bran lacks pigments Durum High protein, Pasta strong gluten, high water absorption
(Atwell 2001)
Part B: Minor Ingredients / 271
Although minor ingredients typically range from 5 to 10% (or sometimes less) on a formula weight basis, they can make or break product success. Within this category, we nd leavening systems — microbial cultures of yeast and/or bacteria, chemical leavening, air and steam. Other ingredients used at this level include dairy products and eggs, added starches and ber enhancement ingredients.
Bakers yeast shows budding scars.(Min-Dak Yeast)
CHAPTER 2
Bakery IngredientsPart B: Minor Ingredients
Ranging from 5 to
10% on a formula
weight basis, minor
ingredients encompass
leavening systems,
dairy, eggs, starch,
fi ber and other
components.
Part B: Minor Ingredients / 271
272 / BAKERY INGREDIENTS
2.B.1. Leavening
Leavening lightens doughs, enhancing the volume, texture, eating quality and often the avor of baked foods. The word “leaven” can be tracked through Middle English’s “levain” to the Latin “levare,” meaning “to raise.” The function of leavening agents is to aerate the dough or batter and make it light and porous. When baked, the porosity translates into the crumb of the nished product. Leavening, thus, also tenderizes the crumb and contributes to the esthetic enjoyment of the nal product by giving it uniform cell structure, bright crumb color, soft texture and enhanced palatability.
The process of leavening involves creating and enlarging the gas cells in dough or batter, cells that expand under the in uence of time and heat to increase the overall size of the dough piece before its starch-and-protein matrix gelatinizes and sets. Mixing incorporates air into the dough mass, thus nucleating the bubbles essential to every style of leavening. Batters cannot create their own cells, only mixing does. Without the bubble nuclii, any gas generated by biological or chemical means would merely dissolve in the free water of the dough. The tiny air bubbles formed during mixing collect the gaseous products of leavening. The more the nucleation sites, the ner the texture of the nished product. While such air bubbles are enough to leaven angel food cakes, nearly every other formulation requires additional leavening gases. The ingredients that contribute leavening effects often provide other functional properties and add to, or detract from, the product’s nal texture, avor and appearance.
Leavens such as bakers yeast, barm or a portion of fermenting sponge consist of living microbes that generate carbon dioxide, ethanol and other volatile organic compounds that ll and in ate the air cells created by mixing. Another category of ingredients
leavens by chemical action. This process combines alkaline baking soda with an acid material such as buttermilk or leavening acids to generate carbon dioxide, which aerates and expands the batter’s volume before the heat of the oven sets its structure.
Not all leaveners are alike in their gassing power, as noted in Table 2.B.01. While chemical leavening releases its gas relatively quickly, there is no further leavening action as with yeast. But yeast may not be ef cient in all baked foods.
2.B.1.a. YeastBiological processes interact with physical and chemical reactions during baking in
a highly complex fashion. Of these, fermentation is the most fundamental, in uencing avor, texture and organoleptic qualities of the nished product, as well as its leavening performance. Most bakery fermentation processes are initiated and sustained by the life forces of a unicellular plant, a fungus actually: the microscopically small yeast. A number of bene cial lactic and acetic acid bacteria also contribute their lives and by-products to the fermentation of baked foods.
Table 2.B.01. Leavening Action of Yeast and Baking Powder Yeast Baking powder*Leavener based on fl our 2.5% 6.0%Leavener based on dough weight 1.47% 3.42%CO2 evolved per g leavener 0.5 g** 0.15g***CO2 evolved per 100 g dough 0.735 g** 0.513 g***CO2 evolved per 100 g dough 350 ml** 214 ml***
* A double-acting baking powder containing 30% NaHCO3 ** CO2 evolution per hour *** Total CO2 evolution (Reed and Nagodawithana 1991)
Part C: Micro Ingredients / 391
When formulation quantities and weighments enter the realm of parts per million (ppm), you know you have reached the micro-ingredient category. Typically used at 5% or less and usually at 0.1% or less, these materials can be diffi cult to measure accurately and so are often combined with other ingredients in packets or as ingredient systems such as bases and concentrates. Some oxidation and fortifi cation ingredients, which are important to achieving proper baking activity and nutritional quality, are added at the fl our mill, using specialized equipment that streams the ingredient at a controlled rate directly into the fl our.
With all micro ingredients, accuracy is essential. Consider the example of fortifi cation
CHAPTER 2
Bakery IngredientsPart C: Micro Ingredients
Used at less than
5%, down to parts
per million, micro
ingredients play vital
roles in fi nished product
quality and shelf life.
Folic acid, shown recrystallized in this photomicrograph taken under polarized light, became a mandatory enrichment in 1998.(Molecular Expressions: Michael W. Davidson, Florida State University)
Part C: Micro Ingredients / 391
392 / BAKERY INGREDIENTS
ingredients. Calcium and folic acid illustrate the physical conundrum of dosing. The US Recommended Daily Allowance (RDA) for calcium is 1,000 mg, but for folic acid, it is 0.4 mg. A slight miscue in dosing will not affect calcium, but it can really throw off the delivery of folic acid.
In a certain sense, micro ingredients represent the baking industry’s equivalent to applied nanotechnology. The defi nition of nanotechnology pegs it as the applied science and technology of controlling matter at the atomic and molecular physical level and employs chemistry, engineering, physics and microfabrication techniques. It involves scales of 100 nanometers or less. (A nanometer is one-billionth of a meter, or 10-9 m. In comparison, a micron, or micrometer, is one-millionth of a meter, or 10-6 m. Thus, 100 nm equals 1 mcm, or 1 μ.) Although bakers do not measure ingredients to parts per billion (ppb), the concept is being studied.
Food nanotechnology is attracting increasing attention among formulators (Tarver 2006), and the Institute of Food Technology issued a Scientifi c Summary on the topic (Weiss et al. 2006). The authors noted that food’s carbohydrate, protein and fat molecules interact through nano-scale participation of their sugar, amino acid and fatty acid components. They suggested the future may see use of nanotechnology for biosensors and functional improvements such as association colloids, nano-emulsions, biopolymers and controlled-release delivery systems.
Controlled release is the whole point of micro-encapsulation, a method of managing ingredient functionality. Encapsulation is the general term covering the enrobing of one material in another at the microscopic scale, and micro-encapsulation describes an even fi ner degree. Ingredient suppliers can count the
Table 2.C.01. Encapsulation Examples Encapsulated ingredient Bakery application ReasonSodium bicarbonate Frozen and refrigerated Prevent premature release doughs; batters Leavening phosphates Frozen and refrigerated doughs; Prevent premature release batters Salt Soft pretzels Prevent premature dissolutionFumaric acid Tortillas Prevent premature carbon dioxide release; prevent formation of translucent spotsVitamins and minerals Fortifi ed bakery products Prevent off-fl avors and loss of viabilityHydrocolloids Muffi ns Prevent sticky doughs during mixingCinnamon Yeast-raised doughs Prevent inhibition of yeastHighly aromatic seasonings (onion, garlic) Frozen and refrigerated Prevent softening of dough during doughs; batters processing; mask strong odors during storageSodium aluminum phosphate Frozen and refrigerated Prevent premature release; doughs; batters prevent graying of dough during storage Natural fl avors and colors General use Prevent fadingEnzyme General use Prevent dusting and exposure of allergens to workers during scaling and addition
(Rask 2003, Rask and Tongue 2006)
Part D: Characterizing Ingredients / 499
Baked foods appeal to consumers in far more ways than as simple remedies for hunger. The infl uences leading a person to select one food over another involve the senses of taste, smell, sight and touch. Even an auditory crunch sends signals to the part of the brain that controls appetite.
Some foods we eat to assuage hunger, but others we consume to satisfy a craving for specifi c taste sensations. In this more or less discretionary consumption, food selection usually ranges beyond staple products and follows more freely the dictates of hedonism.
Characterizing ingredients provide numerous attractive attributes. The appeal of many baked foods is enhanced by this class of ingredients. Prominent among the group of discretionary foods are items such as sweet goods, cakes, cookies, confections and pies. Because the appeal of many of these foods is to a large measure determined by their
CHAPTER 2
Bakery IngredientsPart D: Characterizing Ingredients
Nuts, like all
characterizing
ingredients, add eye
appeal and fl avor to
baked foods.
Part D: Characterizing Ingredients / 499
500 / BAKERY INGREDIENTS
highly fl avored ingredients, the nature and selection of these ingredients play a signifi cant role in determining the level of the acceptability of these foods. In other words: fruits, nuts, spices, fl avors, colors, cocoa, chocolate and other such ingredients add value to baked foods.
2.D.1. Fruits
Fruits are the jewels in the baker’s crown. Their bright colors and pleasing fl avors make them natural partners for the more subtle taste of grain-based ingredients. Bakers can avail themselves of an encyclopedia’s worth of fruits in fresh, frozen and processed forms.
While this discussion looks at several of the most economically important fruits used by bakers, lately several “new” fruits have found a home in the bakery formulary, including acai, banana, guava, mango and pomegranate (Berry 2006). They are worth exploring for their emerging appeal to consumers.
Growers’ federations, boards and councils manage marketing and promotion of many fruit and nut crops grown in the US. These groups generally provide a wealth of information and application resources concerning their crops. They often sponsor research into crop improvement as well as consumer preferences, and some offer grants to support academic-level research about the dietary, nutritional and physiological effects and benefi ts of consuming these crops as food.
The most recent edition of Dietary Guidelines for Americans, released in 2005, recommends that adults eat 2½ cups of fruits and 2½ cups of vegetables every day. Bakery foods can contribute to this.
2.D.1.a. Fresh, canned and frozen fruitsThe US Department of Agriculture (USDA) sets quality grades for
fresh, canned and frozen fruits. Handling of fresh fruits is critical to the quality of fi nished baked goods. Care must be taken to avoid bruising, which opens the fl esh to spoilage microorganisms.
Apples are the pomaceous fruit of the apple tree, species Malus domestica and a member of the rose family Rosaceae. It is one of the most widely cultivated tree fruits, and in the US, the largest producer is Washington State. Roughly 55% of the apple crop enters the retail fresh
market. Bins of apples destined for processors such as bakers are kept in cold storage or controlled atmosphere rooms until needed. An atmospheric content low in oxygen (1%) and carbon dioxide (1.5%) drastically retards the apples’ natural respiration and ripening processes (Deuel 1986). The most popular varieties for bakery use include Granny Smith and Jonathan.
Blueberries are commercially harvested from highbush varieties (Vaccinium corymbosum and V. ashei) and “wild” lowbush varieties (V. angustifolium). The plant is native to North America and grows throughout the northern US and Canada but is now also cultivated in Australia, New Zealand and some South American countries. It is related to the bilberry of Europe. About 60% of the commercial blueberry crop comes
Figure 2.D.01. Native to North America, blueberries from the highbush variety are large in size and sweet-tart in fl avor.(US Highbush Blueberry Council)
Part E: Ingredient Systems / 557
Using and managing ingredients ef ciently presents constant challenges to bakers. Some formulas like classic French bread are simple, requiring only four ingredients ( our, water, yeast and salt), while others like cake doughnuts are quite complex, with 12 to 15 ingredients and sometimes as many as 25 (Smith 1991). Additionally, pro-duction schedules often include products such as multi-grain bread that are made in relatively low volume yet need ingredients unique to that formula.
Both wholesale and retail bakeries, then, are faced with two sources of inef ciency:
CHAPTER 2
Bakery Ingredients Part E: Ingredient Systems
The ineffi ciencies
of hand-weighing
ingredients, some in
quantities measured
in milligrams, prompts
bakers to use bases,
concentrates and
mixes.
Part E: Ingredient Systems / 557
558 / BAKERY INGREDIENTS
the necessity for weighing out a large number of ingredients for a product and ware-housing and handling many ingredients in relatively small quantities. To overcome these inef ciencies, bakers turn to the ingredient systems known as complete mixes, half-and-half mixes, bases, concentrates and pre-mixes.
A complete mix contains everything needed to make a product except water, yeast and sometimes liquid eggs. This is handy in retail shops, where the product may require a special type of our not readily available to the baker. Many wholesale bakers also use complete mixes for certain products, especially cake doughnuts and Danish pastry.
Half-and-half products are mixes that contain all the additive ingredients required plus part of the formula’s our, usually a specialty our such as rye, rice, oat, corn or whole-wheat. The baker supplies the rest of the our from the bakery’s own bulk our stores.
Bases incorporate all formula ingredients except those readily available in bulk to the baker — usually bread or cake our, sugar, yeast and water. Bases are offered in liquid (Figure 2.E.01), paste, plastic (Figure 2.E.02) or powdered form. For example, a roll base may look like shortening, while a sourdough base is often liquid.
Concentrates resemble bases but contain fewer ingredients. The active ingredients are blended onto a base ( our, soy, dry milk solids, etc.) for a dry concentrate or creamed into a shortening or oil carrier creating a paste or plastic material. Usage is generally low: 1 to 5 lb per 100 lb of our.
Pre-mixes, which contain blends of oxidants, yeast foods, enzymes, enrichment vi-tamins and minerals and/or additive ingredients, nd wide acceptance. Formulation accuracy improves tremendously because the addition of such micro ingredients is no longer a matter of many weighments but the addition of a single packet or pouch to
Figure 2.E.01. Biofermented fl avor systems, another style of ingredient system or concentrate, come in liquid form such as this sourdough system. (Puratos)
Figure 2.E.02. Bases are often blended with other materials to form a plastic or paste-like material, shipped in cubes. (Caravan Ingredients)
Table 2.E.01. Mixes and Bases for Bread: A Comparison Ingredient Scratch Mix Base (1:1) Base (2:1) (lb) (lb) (lb) (lb)Flour (spring) 70.00 73.00 41.00 21.00Flour (winter) 30.00 27.00 – –Sugar 8.00 5.00 5.00 5.00Salt 2.00 2.00 2.00 2.00Nonfat dry milk solids 3.00 – – –Mineral yeast food 0.50 0.35 0.35 0.35Shortening 4.00 4.00 4.00 4.00Emulsifi er 0.25 0.50 0.50 0.50Calcium propionate 0.25 0.15 0.15 0.15Vital wheat gluten – 1.00 1.00 1.00Whey – 2.00 2.00 2.00Potato fl our – 2.00 2.00 2.00Soy fl our – 1.00 1.00 1.00Blend weight 118.00 118.00 59.00 39.00 Yeast 3.00 3.00 3.00 3.00Water 65.00 65.00 65.00 65.00Flour – – 59.00 79.0Total dough weight 186.00 186.00 186.00 186.00
(Smith 1991)
Baking Science & Technology / 567
INTRODUCTION
In addition to the ubiquitous wheat ours, bakers use many other grains and seeds in their baked foods. They add them not only for ingredient functionality but also for avor, texture, appearance and a healthy image. Strictly speaking, a “grain” means the seed of the botanical family Gramineae (now renamed Poaceae), usually called the grasses (Morrison and Wrigley 2004). These are the principal cereal grains. In practice, there are several other plant seeds with similar properties that are used by bakers and considered by them as “grains” also and sometimes referred to as “pseudocereals.” And nally, there
A thorough
understanding of the
grains suitable for
baked foods is critical
for formulation and
nutrient claims.
CHAPTER 3
Crops and Their ProcessingBy C.E. (Chuck) Walker, Ph.D., and Jian (Jane) Li, MSDepartment of Grain Science & Industry, Kansas State University, Manhattan, KS
66506-2201. Phone (785) 532-6161; e-mail [email protected] and [email protected]. Published as contribution No. 08-272-B by the Kansas Agricultural Experiment Station.
Bakers work with many cereal grains: (from left) oats, wheat, millet, barley, quinoa, rye and corn.(Getty Images, Christel Rosenfeld)
568 / CROPS AND THEIR PROCESSING
are seeds that do not resemble the cereal grains but that are added to provide unique characteristics (Table 3.01). In addition to incorporating these other grains and seeds into the main dough or batter, they are frequently used as toppings and llings.
This chapter provides a listing of the grains and seeds most commonly used by bakers. For simplicity, we will use the term “grain” for all items discussed. They are listed in alphabetical order, and each in turn is discussed, providing information on the basic grain
properties, where and how it is produced, and how and why it is used by bakers. References are provided to lead the reader to more detailed discussions on each of the grains.
It has been suggested that the habit of nomadic peoples to gather seeds from wild grasses led to the establishment of permanent settlements, agriculture and civilization (Ziehr 1987). At any rate, cereal grains today provide a major portion of our calorie needs, either directly or through feeding them to animals. There are eight cereal grains that are usually listed as widely used for food and feed. They are, in order of world-wide production: corn (maize), wheat, rice, barley, sorghum, oats, rye and the millets.
The naked kernels, or caryopses of the cereal grains with the hull removed, have many similar characteristics in their structure and composition (Figure 3.01). The lengths (diameters) for the various species will vary from about 1 mm to about 10 mm and their individual seed weights from about 1 mg to about 350 mg. Their structures and compositions all share many characteristics.
Table 3.01. Principal Cereal Grains and Oilseeds of World Importance Worldwide grain production (2006-07 July/June crop year) Grain Worldwide Production Top producing Next fi ve leading producing countries US share rank (mmt*) country and shareCorn (maize) 1 704.28 US 37.9% China, EU**, Brazil, Argentina, Mexico 37.9%Wheat 2 593.19 EU** 21.0% China, India, US, Russian Federation, Canada 8.3%Rice 3 418.24 China 30.6% India, Indonesia, Bangeladesh, Vietnam, Thailand 1.5%Barley 4 137.35 EU 40.9% Russian Federation, Ukraine, Canada, Turkey, Australia 2.8%Sorghum 5 56.99 Nigeria 18.4% India, US, Mexico, Sudan, Ethiopia 12.3%Oats 6 23.11 EU 33.4% Russian Federation, Canada, US, Australia, Ukraine 5.9%Rye 7 12.38 EU 52.8% Russian Federation, Belarus, Ukraine, Canada, Turkey 1.5% Oilseeds (2006-07 crop year) Soybeans 1 237.27 US 36.6% Brazil, Argentina, China, India, Paraguay 36.6%Rapeseed 2 46.80 China 27.0% Canada, Germany, India, France, UK1.30%Cottonseed 3 45.82 China 30.4% India, US, Pakistan, Brazil, Uzbekistan 14.6%Palm oil 4 37.02 Indonesia 44.8% Malaysia, Thailand, Nigeria, Colombia, Papua New Guinea ***Peanut 5 32.41 China 45.3% India, US, Nigeria, Indonesia, Burma 4.8%Sunfl owerseed 6 30.15 Russian 22.4% Ukraine, Argentina, France, India, Hungary 3.2% FederationPalm kernel 7 10.27 Indonesia 43.3% Malaysia, Nigeria, Thailand, Colombia, Papua New Guinea ***Copra 8 5.28 Philippines 41.6% Indonesia, India, Vietnam, Mexico, Papua New Guinea ***
* million metric tonnes ** EU: Austria, Belgium/Luxembourg, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Malta, The Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, United Kingdom *** No domestic production of these crops in the US
Table 3.01. While corn leads the world’s crops in production, wheat comes in a close second, and soybeans lead among oilseeds.(USDA 2008a, USDA 2008b)
Baking Science & Technology / 613
CHAPTER 4
Quality LaboratoryIntroduced and updated by Theresa S. CogswellBakerCogs, Inc., Olathe, KS 66062. Phone (816) 820-5364; e-mail [email protected].
INTRODUCTION
From specifying the our, to mixing the dough and through nishing the loaf of bread or any other baked product, it is wise to use objective data to validate consistency and quality to assist production and product development. Maintaining adequate control over composition and functional properties of the ingredients used in the process is an important requisite for producing any type of baked food.
Bakery laboratories
require good staffi ng as
well as instrumentation,
supplies and good
documentation to
accomplish their tasks.
Members of the Interstate Bakeries R&D team evaluate a new formula.(Baking & Snack, Matthews Communications)
Baking Science & Technology / 613
614 / Quality Laboratory
Change is inevitable. Analytical procedures and methods can detect, monitor and track small changes, unseen by the human eye, over time. Maintaining a history of these changes can help make sure you are receiving the quality you are paying for from your ingredient suppliers. But this data can also assist in an investigation to validate a complaint or document a decline in product quality.
Typically, our is the main ingredient on the ingredient legend of any baked food. This key ingredient deserves more attention than simply documenting limits or ranges on an ingredient speci cation to be recorded in a database or stored in le drawer. Flours from different wheat blends, mills and geographic origins can uctuate considerably in their content of protein, ash, moisture, absorption, mix time and functionality. It is essential for the baker to be aware of any changes that may occur in these characteristics before using the our in production. In the automated bakery today, knowing the consistency of our functionality before the mixing process is essential. If the mix time and absorption of each lot of our is not optimized, then the resulting product will not achieve the consistent high-quality product consumers deserve.
Evaluating and approving test methods pertaining to our and other ingredients used by the baking and other cereal-based industries has historically been taken on by AACC International (previously American Association of Cereal Chemists) and AOAC International (previously Association of Of cial Analytical Chemists). Both organizations publish their approved methods in volumes titled, respectively, “Approved Methods of the AACC,” whose 10th edition appeared in 2000 and was updated as of September 2004, and “Of cial Methods of Analysis” (AOAC Methods), whose 18th edition was published in 2004-05.
This chapter will attempt to survey the more pertinent tests relating to our and dough evaluation as they appear in these volumes. Methods that are gaining acceptance in cereal and baking laboratories will also be described brie y even though they may not have gained “of cial” status.
All laboratory work requires precision, especially when handling such a naturally variable ingredient as our. Timing and technique must be impeccable … and reproducible. For this to happen, however, temperature and humidity conditions within the laboratory and its storage areas must be consistent. Whether lab tests support production or product development, reproducibility is critical, and that precision cannot occur when the lab’s ambient conditions vary day-to-day. Climate control is essential.
Remember a short pencil beats a long memory any day. Maintain records of your test results. Data and facts will provide the information needed to run a successful grain-based food company.
4.A. The bake test
By far, the most useful test in the baker’s repertoire is to actually bake with the material being examined, especially our. Various physical and physiochemical our testing methods will report useful information, but ultimately, the bake test yields the most reliable index to the our’s potential performance in production. Although the bake test takes place under standardized and controlled laboratory conditions, its results must still be interpreted according to the variables that normally enter into large-scale commercial production.
Baking Science & Technology / 661
Bakery Sanitation and Regulations
By Richard F. StierConsulting Food ScientistPhone (707) 935-2829; e-mail [email protected].
INTRODUCTION
There are some people who equate sanitation with a bakery looking, smelling and feeling clean. Sanitation is more than that. It is a state of mind and a means of ensuring the products that come out of each and every bakery, whether breads, cookies, cakes, meat pies, pizzas or any one of the myriad of specialty products, are safe, wholesome and t for human consumption. Commitment to good sanitation starts with management and ows down through the plant hierarchy. Management must provide the tools, nancial support and leadership to establish and sustain such commitment. Sanitation is an integral part of the whole quality system, which consists of every operation needed to ensure the
A complete
understanding of
sanitation — its
program, procedures,
systems and tools — is
required to maintain a
safe and secure bakery
operation.
CHAPTER 5
Baking Science & Technology / 661
662 / BAKERY SANITATION AND REGULATIONS
manufacture of safe and high quality baked foods.
5.A. Sanitation: a prerequisite to safe food
The US seafood and juice HACCP (Hazard Analysis, Critical Control Point) regulations state that a HACCP plan should include certain “Prerequisite Programs” (FDA 1995, 2001). These programs may be grouped into six basic categories. These are:
• Sanitation Standard Operating Procedures (SSOP)• Good Manufacturing Practices (GMPs)• Training• Preventive Maintenance• Product Identi cation and Coding• Recall Programs
The HACCP concept was developed in 1959 (although it was not called so at the time) to help establish the potential risk of salmonella in foods and to control that risk. This work was conducted by the US Army Laboratories in Natick, MA, and the National Aeronautic and Space Administration (NASA) in collaboration with the Pillsbury Co., who was a major supplier to the space program. These pioneers realized that existing inspection systems based on nished product testing did not provide the necessary degree of safety. They would need to conduct too much nished product testing to provide that assurance, so the decision was made to develop a system in which safety was built into the process. At that time, there were only three HACCP principles. HACCP has grown through the years to seven principles. It is, as noted above, mandated for certain industries and has become a standard for the whole food industry. It is not yet mandated for the baking industry, but for all intents and purposes it is. Most buyers require that companies from whom they purchase foods or ingredients have a functioning HACCP system.
Even though this chapter is entitled “Bakery Sanitation,” mentioning the two regulations is germane since they formalized the concept of prerequisite programs. When preparing the regulation, the US Food and Drug Administration (FDA) clearly stated that HACCP is not a “stand alone” program. This position is not limited to FDA alone.
The US Department of Agriculture (USDA), which regulates meat and poultry processing, also mandates the adoption of prerequisite programs as part of ensuring food safety. Since there are many bakery items that contain meats, these companies fall under the jurisdiction of USDA. Regulatory agencies and food safety professionals the world over also have taken this stance. HACCP with its prerequisite programs are mandated in the European Union and in many other parts of the world. Finally, prerequisite programs are an integral part of the Codex Food Hygiene guidance document and of the ISO 22000 standard.
Codex Alimentarius Recommended International Code of Practice: General Principles of Food Hygiene not only includes HACCP guidelines but emphasizes the importance of prerequisite programs (UN/FAO 1997). Codex documents are not standards, however. They are guidance documents for international harmonization.
After several years of work, the International Organization for Standardization (ISO) issued its ISO 22000 document (ISO 2005). This document is entitled Food safety management systems — Requirements for any organization in the food chain. The