Page 90 - Statistics presented by Dr. Sara Ismail Aborass

9/8/2023

• According to preparation and lifetime:

Pasteurized milk: 720C For 15 sec kill bacteria (not spores) then cooled very quickly
to less than 3°C (Pasteurized milk will keep fresh for 5-7 days in a fridge)
Unpasteurized - raw or untreated milk
It is recommended that babies, young children, the elderly, pregnant women and anyone
with an impaired immune system should avoid drinking unpasteurized milk.
Filtered milk: Passed through a fine filter to sift out souring bacteria, if unopened
filtered milk can be kept up to 45 days when stored at temperatures of up to 7ºC.

UHT( ultra-heat treatment) milk or long-life milk: heated at high temp (1320C for
two to four seconds and then packaged aseptically.) UHT milk can last six months at
ambient temperatures if unopened. Once opened, it should be refrigerated and treated
like fresh milk.

Dried Milk: in powdered form. Stay up to one year.
Evaporated/ Condensed milk : simply evaporated milk with considerably reduced

water content. Stay up to one year.

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Methods of Milk Analysis

Specific gravity measurement by lactometer. • Measurement of pH.
1.025-1.035 at 25-35∘ C (fresh milk) • 6.6 due to lactic acid.
After 12 hrs of milking, changes to 0.0013

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