Re: What is the effect of fat content on the effectiveness of chymosin and why?

When chymosin is used to coagulate milk, most of the fat ends up in the curd [1]. I believe this is the reason for greater curd mass from whole milk, compared to skim milk.

The presence of fat would not enhance this enzymatic reaction. I think the real question is why the fat ends up in the curd. Is it because it is stuck the casein protein, or because it gets trapped as the curd forms? I don't really know the answer to that question but I suspect it is a little of both.

[1] Fennema, O. 1996 Food Chemistry, 3rd ed. Marcel Dekker, New York.

*Please note: The author is answering on his own behalf, and his answer does not represent a statement from the USDA.