Milk Flashcards
what is milk?
liquid secreted from the mammary gland to serve as nutrition for a newborn
casein
~80% of milk, precipitated by acid or rennin, added to food to improve nutritional value
whey
lactalbumin and lactoglobulin, liquid portion of cheese production, can be used an an emulsifier or added for nutritional value, improves mouthfeel, moisture retention, flavour
fat contributors to…
mouthfeel, flavour, chemical properties
milk has ___% SFA, ___% PUFA, and ___% MUFA
66/4/30
whole milk has ___g fat, 1% has ___g fat, skim has ___g fat, buttermilk has ___g fat
8/3/0/2
what is the only form of CHO in milk?
lactose
lactose intolerance:
inability to digest lactose because of insufficient lactase quantities
symptoms of lactose intolerance:
cramps, nausea, flatulence, bloating, diarrhea
what is a milk allergy?
an allergy to a PRO in milk, usually beta-lactoglobulin
symptoms of a milk allergy:
vomiting, nausea, wheezing, chronic cough, rash, headache
potential health benefits of milk:
decrease in CVD, cancer cell growth, fat mass, contains probiotics
what are the three types of pasteurization?
- regular: heating milk just below boiling point for a short period of time
- ultra: heating milk at a higher temp. for ~15s to extend shelf life
- UHT: heating at an even higher temp. for ~2s then putting it into sterile packaging
homogenization:
mechanical process to break up fat globules into an increased state of emulsion, it coagulated quicker in heat
___% of milk is consumed in fluid form
30
grading is ___
voluntary
___ must be submitted monthly
somatic cell count
storage: fridge for ___ (milk), within ___ days of purchase (yogurt), ___ (buttermilk), a few days (___)
dry storage: ___ (dry, nonfat milk), ___ (ultra pasteurized), ___ (condensed)
< 3wks/10
3-4/sour cream
1yr/3mo
1yr
what factors are possible for cheese classification?
moisture content, milk source, microbial characteristics, appearance, packaging, origin, processing
what are the categories for moisture content (cheese)
fresh, soft, semi-hard, hard, very hard
what are possible milk sources for cheese?
cow, sheep, goat, camel, horse, water buffalo
general steps for cheese production:
- milk selection
- coagulation
- curd treatment
- curing/ripening
what are the two methods for coagulation by acid?
- inoculate milk with bacterial culture (14-16hr)
2. add acid to milk
what are some characteristics of cheese made by acid coagulation?
- low Ca (it’s lost in the whey)
- soft and spongy
- usually not aged
enzymes for coagulation of cheese:
chymosin (aka rennin or rennet)
what are the steps for turn treatment?
cutting (increases surface area, straining follows), heating (increases evaporation to make the cheese firmer, destroys microorganisms), salting (dehydrates, controls bacterial growth, adds flavour), knitting (optional; melting burns into a solid mass), pressing (optional; compacting curds into a mass)
low moisture = ___ curd
smaller
curing
aging cheese in controlled conditions (ex. temperature and humidity)
ripening:
chemical/physical changed that occur during curing
nutritional value of cheese: ___ PRO, ___ fat, ___ CHO, ~___mg cholesterol, ___ soluble vitamins, ___, ___, ___
high/SFA/low
25/fat/Ca/P/Zn
shredability: good for ___
melting
high ___ and high ___ = meltier cheese
fat/moisture
blistering (___ = large, ___ = many small)
aged/unaged
browning is increased with higher levels of:
sugars, amino acids, lactose
stretchability: high ___=tough and grainy, ___=soft
Ca and P/ageing
___ can contaminate soft cheese if not stored properly
listeria
you can freeze cheese for ___ (hard) or ___ (processed)
2mo/5mo
