Ever wondered what the word Pareve (or Parve) written on a food label means? Well then prepare to know.
As it turns out, that you are unaware of the meaning of this label suggests that you're probably not Jewish. Pareve is a Yiddish word meaning something along the lines of "neither meat or dairy, nor prepared with either of these." It's the third category in the kosher triumvirate. Since keeping kosher means not mixing dairy and meat together (kosher Jewish people aren't big on the milksteak), a food item labeled pareve means they can use it together with either a dairy product or a meat product - this pareve product will not lead to the mixing of meat and dairy, in other words.
This may seem obvious, but following a true kosher diet can be tricky. Take soy sauce for example. It should be intuitive that it's neither dairy nor meat, since it's not animal blood and it didn't come out of any udder - it's made from soy, a plant which, along with fish, eggs and grains, forms the basis of the pareve category. So it should be pareve. But one shouldn't take it as such without a Pareve label, which assures the bearer of a bottle of soy sauce that it is indeed pareve and can be used to enhance the flavor of kosher meat without running afoul of the law of God. The reason for this, as the editors of the Jewish Vegetarian Newsletter write in the Spring 1996 issue, soy sauce is a fermented product and as such requires enzymes to carry out the fermentation process. Enzymes can come from a number of sources, including ones from animals (like those derived from pig stomachs, which would make the whole bottle a meat product by kosher standards) as well as from plants (like those derived from the papaya, which would make the soy sauce a true pareve product). This wouldn't be a big problem for someone using meaty soy sauce on their chicken, but if you like soy sauce with your cheese - look out!
It's up to a certifying kosher rabbi, a combination holy man/food inspector/detective to determine not only what products were used in the production of a food, but also the origins of those ingredients. Oh, your papaya-derived enzymes were shipped in a container that was once used to transport chicken hearts? Not kosher! The assembly line for your meat packaging plant also packages butter? Not kosher! Kosher certification is an extremely granular process; there are prescribed shapes and lengths for a knife used to kill a cow and a different one for killing chickens, for example. Since keeping kosher is impossible for an individual consumer on his own within the structure of our modern food supply system, kosher certification groups have organized over time.
Here in the U.S., the oldest group is the Union of Orthodox Rabbis, which arose in the 1920s from an even earlier group that was certifying kosher products before Upton Sinclair published The Jungle and the good idea of having food inspectors caught on as a good idea with everyone. You can still find the Union of Orthodox Rabbis' mark on products today; it's the U in a circle. You'll also likely see a K in a circle in place of or beside it, in which case the Organized Kashrut Laboratories has signed off on the product's kosher status. There are plenty of other competing certification groups but the Circle K and Circle U are the most prominent and likeliest you'll see when you turn your bottle of Yoo-Hoo over.
These certification groups carry on a centuries-long tradition of protecting kosher Jews, vegetarians and other groups that value pure ingredients in their food from being screwed over by food suppliers. In 1660 a Jewish man from Portugal living in New Amsterdam applied for and received the first license to sell kosher meats in North America. By 1796, a kosher butcher became the first to have his license revoked for selling fraudulent kosher meat.