Why is there cow cheese but no pig cheese?

Question

I have always wondered what there is no cheese made by other milks either than cow, goat or sheep. Are they not suitable for humans? Do they taste bad? Is it even possible to make dairy products with them?

Answer

There are several main reasons, historically:

1. Cows, sheep and goats have udders, and can be milked by hand into a bucket. Pigs (or cats, or humans for that matter) have nipples, where you need to suck the milk out. Consider that most of the cheese in the world was invented before machinery was able to create a vacuum, this means that the only option would have been to suck milk from the pig and spit it into the bucket.
2. For making cheese, the fat/protein ratio in the milk is important. It changes, obviously, from species to species, which is why there aren't many hard yellow cheeses made of goat's milk.
3. Remember that it is only people of European descent that really eat dairy as adults. Other people usually can't digest milk after childhood, which is why you don't get Chinese cheese dishes for example. Since cows, sheep and goats are what you find in Europe, that's what cheese is made of. I suspect you could probably get milk from a yak, but no-one makes cheese of it.

Lastly, I have actually had camel's milk ice-cream, which goes to show that it's just a cultural thing mostly.

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