MILK PT 1 Flashcards
what are the most amount of outbreaks from raw milk
three in one year, as seen in 1993, 1994, 1996, 2000; campylobacter jejuni
how many people consume raw milk
2% of people per week; 3.2 million people
what pathogens come from raw milk
brucella, campylobacter, cryptospordium, E. coli, listeria, salmonella
how many outbreaks from 1993-2012 linked to raw milk
127; 1909 illnesses and 144 hospitlizations
what are most raw milk illness outbreaks come from
camplyobacter, shiva toxin-producing e.coli or salmonella; many involve children
how does milk get contaminated
animal feces, bladder infection, cow disease, bacteria, environment, unsanitary processing plant, cross-contamination from dairy workers
whats the only way to kill many pathogenic bacteria
pastuerization
whats the purpose of milk used in foods
improve protein content, moisture, emulsification, texture, color, flavor
describe the composition of milk
primarily water (~87%), remaining is 13% fat and milk solids-non fat like carbs, proteins, micronutirnteints
describe the breakdown of milk solids-non fat
lactose, protein (lactose and whey), minerals
describe carbohydrates in milk
primarily lactose, which is fermented by bacteria into lactic acid which adds flavor to cheeses and fermented milk products
what protein in cheese
casein
describe proteins in milk
caseins and whey
describe caseins in milk
primarily milk protein (80% total protein), predicate when treated with acid or enzymes
describe whey in milk
about 18% of total milk proteins; liquid portion of milk that separates from the curd during cheese production
why is whey used in food insudtry
can isolate whey proteins
what does milk fat do
play major role in flavor and mouthfeel of milk products, like creamy milk chocolate
what does milk fat consist of
triglycerides surrounded by protein and phospholipid membrane
what does phospholipid membrane allow for
colloidal dispersion of fat in acqeous phase
what vitamins in milk
A and D, fat soluble found in milk fat
what are most milks fortified with
A and D, required for fat free milk
what other vitamin does milk contain
vitamin B12 (riboflavin)
what does riboflavin do
degrades underexposure to UV light, which is why milk is packaged in cardboard or opaque containers
what amino acid does milk contain
Tryptophan which is a precursor to niacin (vitamin B3) formation
whats the major mineral in milk
calcium
what are the other minerals in milk
phosphorus, potassium, magnesium, sodium, chloride, sulfur
describe calcium in milk
three cups of milk/day provide substantial portion of DRI
describe color compounds of milk
interfered with light transmission and contribute to opaque, ivory color
what contributes to milk color
fat, dispersed proteins, riboflavin
what about the cow’s diet contributes to milk color
amount of fat-soluble yellow pigments (carotenoids) in plants consumed by cow, which contributes to yellow-ish tinge
what happens to milk from organic farms
more yellow
what is milk grading based on
sight, odor, bacterial count, presence of contaminants (like antibiotics)
describe milk grading in three ways
grade A is highest - most sanitary, voluntary and paid forby dairy industry, grading done by USDA
whats the goal of pasteurization
obtain product that is hygienic and still retains desirable sensory properties
describe milk pasteurization temp
high temp (below BP) and short time
what does pasteurization inactivate
enzymes that cause off-flavors
what does pasteurization destroy
close to 100% of pathogenic microorganisms and 95-99% of nonpathogenic bacteria
what happens to remaining bactera
can convert lactose to lactic acid and cause spoilage
describe the process of heating raw milk
two to four seconds at 275 to 300 F
how long does raw milk stay good
aspecticallt packaging stay fresh from 60-90 days; doesnt beed to be in fridge; stays good as long as any other milk
