Functional properties of Milk

Question 1

4 physical and chemical changes

Answer 1

coagulation
aeration
foaming
gelation

Question 2

what happens during cold storage

Answer 2

beta casein dissociates from micelles into milk serum

Question 3

what associations occur during heat treatment of milk

Answer 3

Conjugation
alpha-lactalbumin and beta-lactoglobulin
K-casein and beta lactoglobulin

Question 4

what happens to caseins when heat is applied

Answer 4

aggregate and Ca phosphate precipitate releasing H+ making it more acidic

Question 5

associations between micelles and whey proteins during the heat are caused by

Answer 5

disulphide bridges
hydrogen bonding
hydrophobic interactions
calcium linkages

Question 6

why arent caseins denatured by heat

Answer 6

their disordered secondary structure

Question 7

what happens to caseins above boiling temperatures

Answer 7

irreversible aggregation
Ca phosphate precipitates
CO2 is expelled
pH is lowered
buffering capacity decreases

Question 8

what temperature are whey proteins denatured

Answer 8

60C

Question 9

four steps to heat-induced whey gelation

Answer 9

unfolding
aggregation
string formation
linkages

Question 10

what do the structure and consistency of whey proteins depend on

Answer 10

pH
protein formulation/concentration
temp/degree of denaturation

Question 11

which protein is the most amphiphilic protein in milk

Answer 11

beta casein

Question 12

why are milk proteins good at emulsifying and foaming

Answer 12

the amphipathic ability of the proteins the hydrophobic is in the fat/air and hydrophillic in the milk solution

Question 13

methods to improve functional properties

Answer 13

enzymatic modification
chemical modification
physical treatment

Question 14

types of enzymatic modifications

Answer 14

cross-linking
amino-acid modification
hydrolysis

Question 15

types of chemical modifications

Answer 15

addition of acid or base
addition of salt
conjugation to other biochemical molecules (fatty acids)