Huh. Never knew this. A quick hunt of the internet says -
"Rennet is derived from one of four sources:
The stomach lining of a calf, ewe or kid (baby goat). The enzyme rennin is found in the stomach lining of animals because it aids in the digestion of their mother's milk. This type of rennet is usually called “traditional rennet” on cheese labels.
Plants, typically thistle
Microbes in fungus and yeast. This type of rennet is called "microbial rennet" on cheese labels
Genetically engineered rennet that imitates animal rennet."
"In cheese making, for milk to separate into curds and whey (curdling), the process requires the addition of rennet. Rennet contains the enzyme chymosin. Rennet is usually sourced from the abomasum (fourth stomach) of newly-born calves whereby the chymosin aids digestion and absorption of milk, adult cows do not have this enzyme. Chymosin is extracted from slaughtered calves by washing and drying the stomach lining, which is then cut into small pieces and macerated in a solution of boric acid/brine for 4-5 days."
So, a lot of cheese won't be vegetarian I guess. It doesn't have meat, but rather an extracted enzyme. I'll read some labels out of interest. Because rennet is made from the bi-product of veal production and consequently a bi-product of the dairy industry, ethically I can't see eating non-vegetarian cheeses as being worse than vegetarian industry... it's the bloody dairy industry again. Calves killed to get the milk have the enzyme taken and are turned into veal.
Yeap, I didn't really do much research. All I knew was "rennet = cow stomach lining".
Just shows, stuff goes into food that you wouldn't expect.
Also, when it comes to things in life where I can't avoid.. say a part of something coming from an animal, I'll try and make that as less of an impact as possible (using as much fake leather as possible, buying second hand if I can) as I have a few different bits of protective equipment that are only made with some leather parts or some wool. Yea it sucks but without shelling out lots and lots of money for custom gear..
Anyway getting off topic, what I mean is wouldn't the specific vegetarian cheese be better? As they wouldn't be getting the money for the calve rennet?