IV C Principles of food production

Question 0

continuous phase

Answer 0

medium surrounding all parts of the dispersed phase

Question 1

what are dispersion systems?

Answer 1

mixture of solids, liquids, gases

Question 2

dispersed phase

Answer 2

distributed throughout the colloidal system

Question 3

a dispersion is classified according to?

Answer 3

the STATE OF MATTER in each phase of the dispersion (i.e. gas liquid solid) OR the SIZE of dispersed particles (small, large, clumps)

Question 4

whipped egg whites are?

Answer 4

gas in liquid: foam

Question 5

sponge cake is?

Answer 5

gas in solid: suspension

Question 6

mayonnaise is?**

Answer 6

LIQUID IN LIQUID: EMULSION

Question 7

gravy is?

Answer 7

solid in liquid: sol

Question 8

custard is?

Answer 8

liquid in solid: gel

Question 9

small particles are?

Answer 9

a true solution (i.e. sugar, salt)

Question 10

large particles are?

Answer 10

a colloidal dispersion (protein, cooked starch)

Question 11

clumps of molecules are?

Answer 11

suspension, separates upon standing (fat, uncooked starch)

Question 12

how to change the degree of dispersion

Answer 12

apply heat or beat

Question 13

what is an interface?

Answer 13

line that forms between two immiscible liquids (water and oil)

Question 14

vegetables are usually (acid/basic) with a (high/low) pH

Answer 14

vegetables: slightly acid, high pH

Question 15

how should vegetables be processed?

Answer 15

at a temperature HIGHER THAN 212F TO DESTROY BOTULISM

Question 16

___________ can be used to can low acid vegetables; why?**

Answer 16

PRESSURE COOKER; reaches temperature higher than 212F

Question 17

relationship between pressure and temperature***

Answer 17

pressure raises temperature

Question 18

if the pH is low/acidic, how should they be canned?**

Answer 18

canned in a BOILING WATER bath

Question 19

____ are sometimes pickled with vinegar or _____***

Answer 19

beets; vinegar or acetic acid - lowers the pH

Question 20

acid causes ___ when green vegetables are overcooked or canned

Answer 20

loss of color

Question 21

what happens when acid is added to green vegetables?**

Answer 21

molecule becomes PHEOPHYTIN (brown or olive green), color fades

Question 22

what happens when alkaline is added to green vegetables?*** (3 things)

Answer 22

1) intense green color = CHLOROPHYLLIN
2) becomes MUSHY (alkaline softens cellulose)
3) WATER-SOLUBLE VITAMINS LOST

Question 23

how to prevent color from fading in green vegetables?***

Answer 23

cook for SHORT TIME- LEAVE LID OFF FOR FIRST FEW MIN to allow escape of volatile acids

Question 24

baking soda- acidic or alkaline?****

Answer 24

alkaline

Question 25

cream of tartar- acidic or alkaline?***

Answer 25

ACIDIC

Question 26

when adding cream of tartar to angel food cake, it maintains a white color. WHY?****

Answer 26

acid prevents the Maillard browning reaction

Question 27

acid in angel food cake has what affect on the volume?***

Answer 27

LARGE volume by STABILIZING EGG WHITE FOAM

Question 28

acid in angel food cake has what affect on the crumb?***

Answer 28

TENDER crumb

Question 29

angel food cake without cream of tartar becomes...?****

Answer 29

TOUGH, YELLOW, SMALL CAKE

Question 30

what are enzymes?

Answer 30

catalysts to facilitate chemical reactions

Question 31

enzymes are what type of molecule? what does this mean?***

Answer 31

proteins- activity will be affected by temperature and pH

Question 32

two types of browning reactions- where do they occur?****

Answer 32

1) enzymatic = cut surfaces of fruit | 2) Maillard = browning of bread or baked goods

Question 33

what happens with enzymatic reaction in ripening of fruit?***

Answer 33

starch --> sugar, softens

Question 34

what causes the browning on cut surfaces of fruit?***

Answer 34

enzymatic oxidation

Question 35

what will acid do to enzymes?***

Answer 35

lowers pH = inhibits enzymes = prevents browning

Question 36

what should you do to vegetables before freezing?***

Answer 36

BLANCH to destroy enzymes --> put in and out of water quickly

Question 37

how to get more rapid browning?

Answer 37

increase pH to 6 or higher, increase temp, decrease water content

Question 38

what is conduction?****

Answer 38

heat moves from one particle to another by CONTACT/TOUCHING

Question 39

good conductors are?***

Answer 39

COPPER, black cast iron, aluminum

Question 40

bad conductors are?***

Answer 40

glass, stainless steel

Question 41

example of conduction -->

Answer 41

meat kept warm on dish sitting on heated pellet

Question 42

what is convection?****

Answer 42

heated air MOVED WITH THE FAN

Question 43

what is induction?****

Answer 43

use of ELECTRICAL MAGNETIC VIBRATIONS TO EXCITE THE MOLECULES OF METAL COOKING SURFACES

Question 44

how does induction work for heating?***

Answer 44

NO open flame; surface DOES NOT get hot.....PAN ITSELF is the original generator of the cooking heat

Question 45

what is radiation?***

Answer 45

INFRARED WAVES coming from glowing heat (gas flame, charcoal, electrical element, toasting, broiling)

Question 46

what is microwaving?***

Answer 46

radiation followed by conduction

Question 47

a microwave affects what type of molecules? how far does it heat into the food?***

Answer 47

water molecules; 2" into food

Question 48

what is standing time of a microwave?****

Answer 48

subsequent distribution of heat by conduction when the magnetron is turned off --> why you have to let it sit!

Question 49

what's a disadvantage of microwaving?***

Answer 49

UNEVEN heat

Question 50

steak on a grill, meat braising in a steam-jacketed kettle = what type of heating?****

Answer 50

conduction + radiation | --- steak on a grill = touching the grill (conduction), radiation from heat moving upward

Question 51

what are engineered foods?

Answer 51

variety of natural and/or synthetic ingredients

Question 52

advantages of engineered foods?

Answer 52

consistent; LONG SHELF LIFE

Question 53

what are meat analogs?****

Answer 53

isolated SOY PROTEIN (ex: imitation bacon bits)

Question 54

properties of meat analogs?***

Answer 54

less fat than meat, about 50% protein

Question 55

what are seafood analogs?***

Answer 55

SOY BLENDED WITH FISH (ex: imitation crab meat)

Question 56

what are vegetable blends?***

Answer 56

feeds people in underdeveloped countries; incaparina and CSM

Question 57

what is incaparina?****

Answer 57

used to feed people in underdeveloped countries; vegetable blend of maize, sorghum, cottonseed flour

Question 58

what is CSM?***

Answer 58

used to feed people in underdeveloped countries; Corn Soy Milk + vitamins and minerals

Question 59

where do molds grow?

Answer 59

warm, dark, damp conditions; grow best on acid, neutral, sweet foods

Question 60

are molds harmful? should you get rid of them, if so how?

Answer 60

- usually don't produce harmful substances | - boil to destroy

Question 61

yeasts need what to grow?

Answer 61

water, energy, acid medium in oxygen

Question 62

how are yeasts destroyed?

Answer 62

boiling

Question 63

what do bacteria need to grow? at what temperature?****

Answer 63

MOISTURE, NEUTRAL FOODS; 68-113F

Question 64

how are bacteria destroyed?

Answer 64

temperatures of pasteurization (145F for 30 min)

Question 65

bacteria danger zone is?****

Answer 65

41-135F

Question 66

can microorganisms grow in frozen foods?

Answer 66

no- prevented by cold temperatures and lack of water

Question 67

do enzymes work in frozen foods?

Answer 67

slow action, but noticeable over time

Question 68

what is dehydrofreezing?

Answer 68

dried to 50% of weight and volume, then frozen

Question 69

how should you thaw potentially hazardous foods?****

Answer 69

1) in refrigerator | 2) submerge under running cold water @70F or lower

Question 70

if you thaw foods in the microwave, when should you cook them?

Answer 70

immediately

Question 71

what prevents growth of microorganisms in dried foods?

Answer 71

low water content

Question 72

do enzymes work in dried foods?

Answer 72

inactivated by blanching

Question 73

what is freeze drying?

Answer 73

frozen first, then water is evaporated without melting crystals (sublimation)

Question 74

how long do canned foods last?

Answer 74

up to a year

Question 75

how are foods canned? why?***

Answer 75

1) if pH is low, acid is high = boiling water | 2) if pH is high, acid is low = pressure cooker (to increase temperature)

Question 76

relationship between acid and bacterial growth***

Answer 76

high acid foods, less bacterial growth

Question 77

best pH for bacteria to grow

Answer 77

neutral

Question 78

how is botulism best destroyed?***

Answer 78

heat in acid (remember: pressure cooking for the veggies that aren't high in acid to increase temperature)

Question 79

calcium compounds are additives in canning used as...?****

Answer 79

HUMECTANTS

Question 80

what are humectants?***

Answer 80

1) retain MOISTURE | 2) increase FIRMNESS, TENDERNESS

Question 81

what is aseptic canning?

Answer 81

food sterilized outside of can, then aseptically placed in sterile cans which are sealed in an aseptic environment

Question 82

what is irradiation?

Answer 82

COLD STERILIZATION to KILL most harmful BACTERIA in foods other than milk (temperature does not raise much even though large amounts of energy are used)

Question 83

what are BHA and BHT?****

Answer 83

ANTIOXIDANTS for fatty products

Question 84

what role do acids play in chemical preservation?***

Answer 84

denature bacterial proteins - interfere with moist or neutral

Question 85

what role do sugar and salt play in chemical preservation?***

Answer 85

make water unavailable