Wednesday, August 18, 2004

A hump in my cheese theory

One month ago today (it's Rosh Chodesh again) I suggested that perhaps the reason non-kosher milk doesn't coagulate, and thus can't be used to make cheese, is related to the biological fact that "the milk of ruminant animals differs from non-ruminant milk".

I don't have any more scientific evidence for that claim today than I did then, but I did want to get over a little hump in my theory. Anyone paying attention to last week's parasha would have noted the inconvenient fact that camels do chew their cud*, though they (and their milk) are non-kosher.

Fortunately, there is an explanation. Despite claims you may find at certain websites, camels are not true ruminants. Unlike cows, sheep, goats, deer, gazelles, giraffes, buffaloes and others, camels have only three stomachs.

Whether this explains the cheese question remains a mystery, at least to me, since I don't know what is it about rumination that inhibits coagulation.+

*Note that hares and hyraxes, though mentioned along with the camel as chewing the cud, clearly do not ruminate the way cows do; they just sometimes rechew their food.

+Actually, I don't know much about rumination at all, or coagulation for that matter. That's the magic of blogging - you can get attention without having to know what you're talking about.


Anonymous said...

"Pig milk contains about 6.8 percent fat, 2.8 percent casein, 2.0 percent whey protein, 5.5 percent lactose, and 1.0 percent ash. Thus, from a composition point of view it is a fairly rich milk. However, since the pig is a nonruminant, the milk fat will be primarily long-chain fatty acids (probably a lot of C16:0). The short-chain fatty acids that provide the typical flavor to dairy products produced from ruminant milks (e.g. cow, goat, sheep, etc.) would not be present in pig milk. The fatty acid composition of the fat in the milk from pigs will be a function of the diet of the pig, just like it is for milk fat in human milk. Thus, I don't think there is much of a future for pig milk cheese." - Dave Barbano, Cornell Prof. of Food Science


"Many non-ruminant mammalian species regulate synthesis of short- and medium-chain fatty acids (SCFA and MCFA, respectively) by a specific enzyme (thioesterase II) which cleaves the MCFA from the fatty acid synthetase (FAS) enzyme complex (Smith, 1980). However, ruminants do not possess this enzyme; rather, the mammary gland FAS exhibits both medium-chain thioesterase and transacylase activity (Knudsen and Grunnet, 1982)"

and finally:

Zman Biur said...

Yes, I cited Prof. Barbano in my original post.Your second reference is new to me, though.


Zman Biur said...

Also, I don't see any discussion in the sources you cite about whether the differences in composition between ruminant and non-ruminant milk should be expected to affect the coagulation into curd. That's what I'm mainly looking for. Thanks again!