pertemuan 1_basic processes.ppt

7/27/2019 Pertemuan 1_Basic Processes.ppt

1/18

31/10/2013 1

BASIC UNIT OPERATIONS

IN FOOD PROCESSING

The processing operation in manufacturing of

food products varies depending on type of

products or raw materials There are many operations commonly applied

in most processing of food products, e.g.

material handling, cleaning, sorting, grading,

peeling, mechanical separation, size reduction,

mixing, forming, packaging.


2/18

31/10/2013 2

Material Handling

Movement of raw materials or products during storageand processing

Care must be taken to :

- maintaining sanitary conditions or

minimizing contaminations

- maintaining raw material/product quality

- minimizing raw material/product loss

- minimizing microbial growth

Factors concerned : time, temperature, humidity

Equipment : conveyors, elevators, trucks, pneumaticequipment, pump


3/18

31/10/2013 3

Cleaning

Removing contaminants

Wet cleaning : soaking, spraying, flotation washing and

ultrasonic cleaning

Dry cleaning :Separation by air, magnetism or physical

methods


4/18

31/10/2013 4

Sorting

Separation of foods into categories on the basis

of a measurable physical property

Shape & size sorting

Color sorting

Weight sorting


5/18

31/10/2013 5

Grading

The assessment of a number of attributesto obtain an indication of overall quality of

food

By trained operators, for example :

Meats are examined for tenderness, fat

distribution, carcass size

Wheat flour is assessed for proteincontent, dough extensibility, color


6/18

31/10/2013 6

Peeling

Removing unwanted materials and to

improve appearance of the final product.

Flash steam peeling

Knife peeling

Abrasion peelingCaustic peeling

Flame peeling


7/18

31/10/2013 7

Mechanical Separation

Centrifugation

Filtration Expression


8/18

31/10/2013 8

Centrifugation

The separation of immiscible liquids (suchas an oil-in-water emulsion), or solids fromliquids by application of centrifugal force.

Equipment :

Liquid-liquid centrifuges

Centrifugal clarifiersDesludging, decanting or dewatering

centrifuges


9/18

31/10/2013 9

Filtration

To clarify liquids by the removal of smallamounts of solid particles (for examplewine, beer, oils and syrups), or

To separate liquids from the solid part ofa food by cake filtration (for example fruit

juices)

Equipment:Pressure filters

Vacuum filters


10/18

31/10/2013 10

Expression

The extraction of oils and juices. It is

frequently combined with size reduction

to maximize the yield of product

Equipment :

Batch presses

Continuous presses


11/18

31/10/2013 11

Size Reduction

Size reduction of solid foods

Size reduction in liquid foods


12/18

31/10/2013 12

Size Reduction of Solid Foods

Chopping, cutting, slicing and dicing

Large to medium ( stewing steak, cheese, slicedfruit canning)

Medium to small (bacon, sliced beans and dicedcarrot)

Small to granular (minced or shredded meat,flaked fish or nut and shredded vegetables)

Milling to powders or pastes of increasingfineness


13/18

31/10/2013 13

Size Reduction of Liquid Foods

Emulsification or homogenization (mayonnaise,milk, essential oils, butter, ice cream and

margarine)

Equipment :

High-speed mixers

Pressure homogenizersColloid mills

Ultrasonic homogenizers


14/18

31/10/2013 14

Mixing

To obtain an uniform mixture from

two or more components

Solids mixing

Liquids mixing


15/18

31/10/2013 15

Mixing

Equipment :

1. Mixer for low- or medium-viscosity liquids :

paddle agitator, impeller agitators, powder-

liquid contacting devices2. Mixer for high-viscosity liquids and pastes :

vertical-shaft impellers, twin-shaft horizontal

blades planetary mixers, continuous rotor-

stator mixers, multi-agitator systems

3. Mixer for dry powder and particulate solids :

tumbling mixers, ribbon mixers, vertical screw

mixers


16/18

31/10/2013 16

Forming

To mould foods that have a highviscosity or a dough into a variety ofshapes and sizes

Many designs of moulding and formingequipment made specifically forindividual products.

Bread mouldersPie and biscuit formers

Confectionery moulders

Extruder


17/18

31/10/2013 17

PackagingTo protect foods from microbial cantamination,

physical dirt, insect invasion, light, moisture

pickup, flavour pickup, moisture loss, flavour

loss, physical abuse, attractiveness and labeling

Ex. Metal can, glass/plastic bottle, paper andpaperboard, plastic/metalic film, laminates


18/18

31/10/2013 18

pertemuan 1_basic processes.ppt

Documents