FOOD PROCESSING

Question 1

WHY PROCESS FOODS?

Answer 1

1. EXTEND SHELF LIFE
2. MAINTAIN SENSORY PROPERTIES
3. MAINTAIN OR IMPROVE NUTRITIVE PROPERTIES
4. ENSURE SAFETY
5. MAKE MORE CONVENIENT
6. BOTTOM LINE: $$ (ECONOMIC VALUE)

Question 2

HEAT PROCESSING

Answer 2

Use of high temperatures to destroy enzymes

and microorganisms that could reduce quality and/or safety of food

Question 3

What type of HEAT PROCESSING

Answer 3

BLANCHING
PASTEURIZATION
COMMERCIAL STERILIZATION
STERILIZATION

Question 4

A mild heat treatment that primarily destroys
enzymes and reduces microbial load (does not necessarily kill pathogens), further preservation methods needed to extend shelf life.

Answer 4

BLANCHING

Question 5

A mild heat treatment used primarily to destroy pathogenic organisms but it also destroys enzymes and reduces microbial load.

Answer 5

PASTEURIZATION

Question 6

Example of BLANCHING

Answer 6

Vegetables, frozen, canned

Question 7

PASTEURIZATION

Requires an addition preservation method to extend shelf life example

Answer 7

refrigeration, drying

Question 8

STERILIZATION

Answer 8

• A very severe heat treatment that destroys all microorganisms.

Question 9

A severe heat treatment that destroys pathogenic and many microorganisms that could spoil food.

Answer 9

COMMERCIAL STERILIZATION

Question 10

COMMERCIAL STERILIZATION Extends shelf life, room temperature stable example

Answer 10

.canned foods

Question 11

METHODS OF HEAT TRANSFER

Answer 11

CONDUCTION
CONVECTION
RADIATION

Question 12

Heating of solids; Slow heating; Heating of fixed molecules in a row.

Answer 12

CONDUCTION

Question 13

CONDUCTION Examples

Answer 13

spoon in sauce pan.

Solid pack pumpkin in a can.

Question 14

Faster heating of liquids and gas; Hot liquids and gasses raise, cooler portions sink, creating a flow or
current.

Answer 14

CONVECTION

Question 15

Examples of CONVECTION

Answer 15

forced air heating in houses; Canned juices.

Question 16

Electromagnetic

waves.

Answer 16

RADIATION

Question 17

RADIATION Two general types:

Answer 17

1- Heat radiation from a heat source.

2- No heat radiation that causes the food to heat up.

Question 18

No heat radiation that causes the food to heat up

such as

Answer 18

1- Microwaves
2- Irradiation that does not transfer heat: Gamma
rays, x-rays, electrons (E-beam), Ultraviolet).

Question 19

Heat radiation from a heat source.

Answer 19

Flames:
campfire, hot dogs, hamburgers, BBQ.
Infrared.

Question 20

FACTORS INFLUENCING CHOICE OF HEAT TREATMENTS

Answer 20

1. Type of food
2. Level of contamination
3. Presence of oxygen
4. Heat resistance of organisms or enzymes
5. Heat penetration
6. Packaging material
7. Size of container
8. Sensory qualities desired

Question 21

In medium & low acid (>4.5 pH) Foods, the canning process is designed to kill

Answer 21

C.Botulinum.

Question 22

Low acid

Answer 22

5.0 - 6.8.

Meat, dairy, vegetables

Question 23

Medium acid

Answer 23

4.6 - 5.0.

Soups, vegetables

Question 24

Acid

Answer 24

3.7 - 4.5.

Fruits

Question 25

High acid

Answer 25

2.3 - 3.6 | Citrus fruits, berries

Question 26

OBJECTIVES BLANCHING OF FRUITS AND VEGETABLES

Answer 26

1. Inactivate enzymes 2. Lower microbial load (combination of rinsing action and heat) 3. Aids in packaging – wilts vegetables and removes respiratory gases 4. Removes dirt, leaves, etc. 5. Aids in peeling

Question 27

Inactivate enzymes

Answer 27

A. Metabolic B. Maintain color C. Texture D. Flavor | E. Nutritive value

Question 28

GREEN BEANS: Become mushy upon high heat treatment. Therefore, one way to keep them firmer is to

Answer 28

activate Pectin Methyl Esterase (PME)

Question 29

DRY BEANS: Must be partly rehydrated before

Answer 29

blanching

Question 30

ADEQUACY OF BLANCHING:

Answer 30

``` Enzyme tests: • Peroxidase • Catalase • Lipoxygenase Physical: • Wilting • Color ```

Question 31

PASTEURIZATION Used for

Answer 31

milk, liquid eggs, fruit juices | and beer.

Question 32

Function of PASTEURIZATION

Answer 32

 Destroy pathogens  Reduce microbial load  Inactivate enzymes  Extend shelf life

Question 33

Low-Temperature Long-Time | pasteurization (Vat):

Answer 33

145° F (62.8° C) for | 30 minutes

Question 34

High-temperature short- | time (HTST) :

Answer 34

161° F (71.7° C) for 15 seconds • 191° F (88.3° C) for 1 second • 194° F (90° C) for 0.5 second

Question 35

Ultra-high temperature (UHT):

Answer 35

275-284° F (135 to 140° C) for a few seconds

Question 36

CREAM

Answer 36

150-155° F (65.6-68.3° C) For 30 minutes | 166-175° F(74.4-79.4° C) For 15 seconds

Question 37

EGG PASTEURIZATION: Based upon

Answer 37

killing and preventing growth of salmonella

Question 38

MILK PASTEURIZATION: Based upon

Answer 38

T.B. Microorganism

Question 39

Liquid eggs PASTEURIZATION heated to

Answer 39

140-144° F(60-62° C) and held for 3.5-4.0 minutes