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Food Science 210 > Thermal Processing > Flashcards

Flashcards in Thermal Processing Deck (69)
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1

types of thermal processing?

cooking, blanching, pasteurization, sterilization

2

most widely applied unit op in food processing?

thermal processing

3

three basic mechs of heat transfer?

conduction, convection, radiation

4

conduction is heating of ___, convection is heating of ___

solids; fluids

5

examples of radiation?

infrared, microwave, dielectric

6

primary objective of cooking?

increase palatability

7

baking and roasting happen at _____degrees, frying happen at ____ degrees

150-200; 175-225

8

cooking inactivates ____ factors like ___ in pulses

anti-nutritional factors; lectins

9

___ bioavailability reduced by ___ browning

lysine; Maillard (non enzymatic)

10

these vitamins decrease in bioavailability but not concentration with cooking

vitamin A and D

11

these vits decreases in both [ ] and availability

thiamine, niacin, folate

12

primary purpose of blanching?

inactivate deteriorative enzymes, kill spoilage bacteria

13

blanching usually done on __ foods, prior to ____

solid; freezing/canning

14

blanching reduces ___ by removing tissue gases

volume

15

blanching of fruits before ___ allows surface ___

drying; pasteurization

16

blanching inactivates these deteriorative enzymes

LOX (lipoxygenase), polyphenol oxidase (PPO), pectinase

17

pectinase ___ plant tissues

softens

18

blanching is referred to as :

hot break process

19

loss of nutrients during blanching is mainly due to;

leaching (loss of ascorbic), thermal destruction, oxidation

20

what is observed as indicator of severity of blanching?

loss of ascorbic acid

21

A heat treatment which kills part of the microbial population present in food

pasteurization

22

target pathogens in pasteurization in milk?

tuberculosis (old), coxiella burnetti (new)

23

What are the two processes in pasteurization?

LTH, HTST

24

LTH is at __ degrees for ___ minutes; HTST is at ___ degrees for ___ seconds

63; 30; 72; 15

25

Is LTH or HTST more detrimental to nutritional/sensory properties?

LTH

26

2 processes in pasteurization?

batch (small), continuous (large)

27

equipment used in continuous process?

PHE (plate heat exchanger)-->high production rate, no overheating

28

why is PHE corrugated?

for more surface area-->more points of contact

29

foods that are pasteurized?

milk, beer, juices, eggs

30

process used in canning, retorting, and ultra high temp processing

sterilization (appertization)