Dairy and Milk Science 2017 Flashcards
What is the VAT method?
Pasteurization
batch of milk pasteurized at one time
Min 145F for 30 mins required
used for sour cream and yogurt
What are the specific VAT batch temperatures? (6 microorganisms)
Diphtheria bacteria can be destroyed at 130F for 30 mins
Tuberculosis 139F
Streptococcus 133F
Typhoid 136F
Salmonella 130F
Q-Fever 145F
What is the high temp short time method?
Pasteurization
Milk introduced to coninuous flow process which milk is carefully heated at 161F for 15 sec, 166F for 15 sec(for Q Fever control)
for high fat products, ie cream, 175F for 25 sec
What is high heat short time method?
Pasteurization
heats from 191-212F
What is the ultra high temp method?
Pasteurization
In a vacuum
temp rises to 194F for 3/4 second
useful for high sugar/fat products such as 50/50 milk and whipping cream
big benefit is increase to storage life
What is the instantaneous method?
Pasteurization
heats to 280F for a fraction of a second
used in non-fridge dairy creamers
What is Grade A milk? Raw milk
min <50,000 bacteria/mL
used for cooking in industry
usually cooked to 200F but not pasteurized
What are requirements for Grade A milk for pasteurizing?
min <20,000 bact/mL
What are the standards for grade B milk, raw milk and for pasteurizing
raw milk - min <1,000,000 bact/mL
for pasteurizing - min <50,000 bact/mL
What are the standards for certified raw milk?
min <3,000 bact/mL (CA strict)
regular bacterial testing
certified means that dairy/distributor certifies milk is clean and free of pathogens
vet on site for health of cows
What are requirements for dry milk?
it’s powdered
grade A min <30,000 bact/mL
What happens to homogenized milk?
breaks up fat globules into a non-settling liquid in the centrifuge
How is homogenized milk checked?
checked with one quart milk bottle
draw 100 mL
test top and bottom of milk after settles
should not differ in fat content by more than 10% as well as no visible cream line after 48 hours in cold storage
What are the regulations on water in regards to milk?
adding additional water to milk is illegal
device cyroscope tests freezing point
What is the phosphatase test?
determines pasteurization efficiency
raw milk contains phosphatase which becomes inactivated with proper pasteurization
