Food Science

Ag Processing TechnologyUnit 1

Agriscience: Fundamentals and Applications Unit 33

Objective To explore the nutrient requirements for

human health and the processes used in food science to ensure an adequate and wholesome food supply

Introduction Food: a material containing or consisting

of carbohydrates, fats, proteins, and supplementary substances such as minerals

This unit is to explores the foods that humans need to maintain health and sustain growth and how those foods reach our tables from their beginings as raw products

Reading Assingment Read p. 639-643 (Stop at Food Customs of

Major World Populations)

Food Customs of Major World Populations Availability of food and technology to

prepare that food dictates eating habits What are the eating habits of these major

world populations Asia Mexico United States

Methods of Processing, Preserving and Storing Food Oldest ways are fermenting and pickling Controlled fermentation is used to produce

Cheese, wines, beers, vinegars, pickles, sauerkraut

Primary Objective of Processing and Preserving Change raw commodities into stable forms Due to refrigeration and various

processing techniques we now expect almost all foods to be available at any time during the year

But do they always taste as good?

Slowing Deterioration Tomatoes and cucumbers that will be sold raw are waxed to

retard shriveling while they are in the grocery store Apples are treated with decay inhibitor Grapes are fumigated with sulfur dioxide to control mold Silos where grain is stored are purged with 60% carbon

dioxide to control insects Carbon dioxide inhibits the growth of bacteria and is used in

the process of controllled atmosphere, an example is the preservation of lettuce—it is transported in a controlled atmosphere to keep the edges from turning brown

Humidity should also be controlled for optimum storage

Other Ways of Slowing Deterioration Refrigeration Blanching Canning Dehydration Freeze-drying Oxidative deterioration Dehydrofreezing Irradiation

Packaging That Can Improve Shelf Life Cardboard Boxes Molded Pulp trays to prevent bruising Plastic wraps Retortable pouches provide protection

from light, heat, mouisture and oxygen transfer Flexible, consist of two layers of film with a

layer of foil between them Benefits—increased shelf life (1-2 years)

Potatoes Potatoes are offered up to us in a variety

of ways Raw Fried Frozen Cooked & canned Dehydrated

We are going to dehydrate our own potatoes and then compare them (taste, texture, look, etc) to raw, fried, frozen and cooked & canned potatoes.

Food Additives to Enhance Sales of Food Commodities Processing may reduce the natural

nutritional value of the product To compensate for that loss vitamins and

minerals are added back in to restore nutritional value

Sugar is the most widely used food additive.

Reading Assingment Read Food Preparation Techniques

Food Products From Crops

Food Products from Crops Food from plants help meet body

requirements for food in four of the five food groups

Fruits, Vegetables, Nuts Nearly ready to eat at harvest Processing can be as simple as picking,

washing and eating or the foods may take a journey through many processes

Cereal Grains Compose the major diet of the world Economical to process because they can be left

on the plant until nearly dry However, each year much of the worlds food grain is lost

due to rotting in the field, improper storage, birds, insects and rodents

WHY???? Grain processing means separating or milling the

grain in to its basic parts- hulls, bran, flour and germ

These components are then used to make cereal, bread, pasteries, pasta and thousands of other products

Oil Crops Soybeans, cottonseed, peanuts, rape, palm nuts, coconuts,

olives and corn are all rich in vegetable oils These oils are used for cooking, frying, baking, and for

other food products such as dressings, coffee creamers, shortening

Also used to make industrial products such as paints, laquers and plastics

Seeds, nuts and other oil rich parts are crushed or ground and heated

The oil is extracted by solvents and purified for food and industrial uses

The meal is dried and ground and used for livestock feed See fig. 33-15 on p. 651

Food Products From Animals

Food Products From Animals Meats Fish Poultry Dairy

Dairy Products 37% of milk consumed in the US is in the

fluid form Remainder is used to make cheese, butter,

frozen foods, dried whole milk, cottage cheese, evaporated milk and condensed milk

Milk and Milk Products Major componenets

Water Fat Protein Sugar minerals

Milk and Milk Components: Water Makes up 88% of fluid milk Water is the carrier for disolved,

suspended and emulsified components

Milk and Milk Componenets: Protein Milk provides a substantial portion Predominante protein: casein

Casein is found only in milk Makes up about 82% of the milk protein Exsists in suspended form and is easily

coagulated by the action of acids and enzymes High quality Contain all the essential amino acids in

proper balance for good nutrition

Milk and Milk Components: Milk Fat Concentrated sources of energy Many different fats that give milk its

distinctive, pleasing flavor High in fat soluable vitamins- A,D, E, K

Milk and Milk Components: Lactose Major carb of milk Makes up ½ the nonfat solids in milk Relative sweetening power of lactose is

about 1/6th that of sucrose (common table sugar)

Milk and Milk Components: Minerals Contains 7 major minerals and several in

minor and trace amounts Calcium and phosphorus

Essential to human nutrition for building bones and certain metabolic processes

Milk is the chief source of calcium in the diet in the US

Phosporus is contained in the same biological relationship to calcium as occurs in the growing skeleton

Recommended daily amounts of dietary calcium can not be met without using milk

Milk and Milk Components: Vitamins All vitamins required by humans are found in milk Some are fat soluable and are associated with butterfat,

those that are water soluable are found in the non-fat portion of milk

Vitamin A and carotene are present in high concentrations Carotene gives milk its color

Vitamin D content of fresh milk is low Commercially pasteurized milk is fortified with Vitamin D to

balance the product for optimum nutrition Abundant source of riboflavin (Vitamin B2) Important source of niacin because it is in fully available

form Significant amount of thiamine (Vitamin B1), biotin, vitamin

B12, folic acid, choline

Processed Milk Products Fluid milk

sold pasteurized for safety and homogenized to keep the milk fat in suspension

Whole milk is sold with 3.5% milk fat 2%, 1% and non-fat (skim) milk are also available Fortified (A & D) milk is also sold

Cream Component of milk that contains up to 40% butterfat Butter is made from cream Made by concentrating the fat portion of the milk by

running it through a seperator Whipping cream is 40% fat, table cream 18-20%, Half

and Half approx. 12%

Processed Milk Products Ice cream, ice milk and sherbet Nonfat dried milk

Used for humans and animals Often used in dairy and other food products

Cheese Made by exposing milk to certain bacterial

functions or by exposing it to enzymes Both methods coagulate some of the proteins

found in milk Many types and varieties of cheese

Processed Milk Products Cottage Cheese

Made from skimmed milk Condensed and evaporated milk

Both are canned Produced by removing large portions of water

from whole milk using a vacuum pan Condensed milk is further treated by adding

sugar This makes condensed milk important to the baking

and ice cream industries

Meat Products Beef Lamb Pork Poultry Fish Game All are processed by slaughtering the

animal and then dressing the animal for market purposes

Beef Slaughtering Process Render the animal insensible

This is done to comply with the Humane Slaughter Act of 1958 Several methods of accomplishing this

Single blow Gunshot Electrical current Carbon dioxide gas

After the animal is insensible to pain it is shackled, hoisted and stuck in a large artery to permit bleeding

The head may also be removed during or following the bleeding

Removal of the hide is next. It is cut open at the midline of the belly and a mechanical hide puller pulls the hide off in one piece.

The Breast and rump bones are also split at this time by sawing

Beef Slaughtering Process All the internal organs or viscera are

removed, except for the kidneys All USDA regulated plants must inspect the

carcass and the viscera to confirm good health Next the hide is split down the center of

the backbone and washed with warm water

The carcasses are then shrouded and cooled for a minimum of 24 hours before the carcass is ribbed and further processed

Aging Beef To age or ripen means to leave the carcass

undistrubed for a period of time while the beef cools.

Fresh beef is not in its most tender state immediately following slaughter so aging allows the natural biological changes to occur that change muscle to meat

3 methods of aging Traditonal Fast Vacuum Packaging

Time, temperture and technology help define these three methods

Selling Beef Sold in three ways

Block beef Shipped in exposed halves, quarters or wholesale cuts to

be cut into retail cuts at the supermarket Meat is ready for sale over the “block” or counter This method creates concern over sanitation, shrinkage,

spoilage and discoloration Fabricated boxed beef

Carcass is divided into smaller cuts, vacuum sealed, boxed, moved into storage and shipped to retailers

Processed meats Scraps that are not suitable for sale over the block. These meats have the bones removed and are sold as

boneless cuts. They are also canned, made into sausage, dried or smoked.

Sheep Rendered insensible and bled Front feet, pelt, head, hind feet are

removed Carcass is opened and eviserated Because a lamb carcass is small the front

legs are folded at the knees and held with a skewer

Washed and cooling procedures are similar to those used with beef

Hogs Rendered insenible Shackled and hoisted and bled Carcass is then plunged into 150 degree water for 4

minutes to loosen the hair The carcass is then dehaired by a dehairing machine The hog is then returned to the rail where it is washed and

singed and the head is removed Next the carcass is opened, eviscerated and split Leaf fat is removed

Leaf fat is the fat inside the body It is used to make lard which is used in cooking and baking

Kidneys and facing hams are inspected Carcass is sent to a 34 degree cooler

Poultry Bird is secured to a conveyor belt and bled Next the animal is scalded and then picked After picking the bird is singed to remove

the fine hairs that cover the bird under the feathers

Bird is washed, eviscerated and the giblets are cleaned

Bird is then cooled to 40 degrees usually with ice

Fish Processing procedure depends on the type

of fish Evisceration, scaling and head removal

along with washing and cooling all occur Process really depends on how the fish is

to be consumed For example:

Tuna can be left whole or cut up and processed Shell fish like crab and lobster are kept alive

until cooking

Game Processing begins in the field Same basic processing procedure is

followed Most are processed by hunters or small

hometown lockers instead of big processing plants

Large game is processed in a fashion similar to cattle

Fowl are dressed in a fashion similar to poultry

Kosher Slaughter Kosher: right and proper Based on the religious ritual of the Jewish faith Animals must be killed by a rabbi or specially

trained repersenative Methods and time by which the meat must be

sold are based on ritual that relates to concern for sanitation

Meat must be consumed quickly and neither packers or retailers can hold kosher meat for more than 216 hours (9 days)

Washing of the meat is required every 72 hours

Major Cuts of Meat Different areas of the animal are useful for

different purposes See fig 33-22, 33-23, 33-24 Quizzes

Learn the Major cuts of meat for beef, pork and lamb

Use the worksheets and this book to help you study

Quiz 1 will be on the beef on January 30 Quiz 2 will be on the lamb on February 6 Quiz 3 will be on the pork on February 13

By-Products All parts of the animal are not edible Dressing percentage is a term used to indcate the

percentage or yeild of hot carcass weight to the weight of the animal on foot

Offal is removed from the live animal to arrive that the dressing percentage

Formula: hot carcass weight divided by the live weight of the animal

For example: HCW= 900 lbs LW= 1500 900/1500= 0.6 or 60% DP

What happens to the offal?XXXX Accounts for many products that are used daily and can be

divided into 12 categories Hides Fats Variety Meats Hair Horns and Hooves Blood Meat Scraps Bones Intestines and Bladders Glands Collagen Contents of Stomach

Hides Leather products

Shoes Harnesses Saddles Belts Clothes Sporting Equipment Hats Gloves

Fats Oleomargarien Soaps Animal feeds Lubricants Leather dressing Candles fertilizers

Variety Meats Heart, liver, brains, kidneys, tongue, cheek

meat, tail, feet, sweetbreads (thymus and pancreatic glands), tripe (pickled rumen) are sold over the counter as variety or fancy meats

Hair Artists brushed Toothbrushes Paint brushes Mattresses Upholstery Air filters Baseball mits

Horns and Hooves Carving medium Fashioned into decorative knives, umbrella

handles, goblets, combs and buttons

Blood Used in refining sugar Stock feed Shoe polish

Meat Scraps and Muscle Tissue Meat meal Tankage

Dried animal residue used in feed and fertilizer

Bones Some put the same uses as horns and

hooves Stock feed Fertilizer Glue

Intestines and Bladders Sausage Lard Cheese Snuff Strings for musical instruments Tennis rackets

Glands Medical drugs

Collagen Glues Gelatin Used in various forms in the industries of

Furniture Photography Medical Baking

Stomach Contents Feed Fertilizers

New Food Products on the Horizon New foods and new versions of familiar

things arrive daily Scientist and technology are striving to

make what we eat better for us and also working to keep food cost low

Convenience foods are on the rise and will continue to become more important to us in the future