ANIMAL PHYSIOLOGY
DIGESTION IN DIFFERENT ANIMALS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a coenzyme must be added to the milk
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the pH of the milk must be lowered
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heat must be applied to the milk
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rennin cannot coagulate milk
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Detailed explanation-1: -Reducing milk pH to 6.3 caused a significant decrease in coagulation time but a less marked increase in curd firmness. The greatest increase in curd firmness was obtained by a combination of reducing milk pH, addition of . 02% calcium chloride, and reducing chymosin concentration.
Detailed explanation-2: -RENNIN has an optimum pH of 3.4 for the proteolysis of bovine serum albumin1 and 3.8 for poly-L-glutamic acid2. At pH values between 5 and 7 it will coagulate milk and slowly attack casein. It has maximum stability at pH 5.4, while at values above 7 it loses activity rapidly.
Detailed explanation-3: -Milk coagulates spontaneously at various pH zones, insoluble casein salts being formed between pH 2.0 and 3.0, isoelectric casein at pH 4.7 and calcium caseinate at about pH 6.5. Optimum rennet coagulation is at about pH 6.0 coinciding with complete conversion of casein to paracasein.
Detailed explanation-4: -During cheesemaking, the pH of cheese milk is decreased slightly before renneting, which speeds up the coagulation process (Zoon et al., 1989).