I had no idea, until I read a fascinating piece by Patricia Marx in the New Yorker, that one and a quarter billion dollars in kosher-certified ingredients are exported worldwide from China each year. There is an abstract of the article here (you have to subscribe to get the full text), and here are some of Marx's observations:
...Dozens of mashgihim (kosher inspectors), have been crisscrossing China for decades, eyeing the goings-on in hundreds of factories to insure that the ingredients and the production methods are in accord with kashruth (Jewish dietary laws). Thus, they ask: Does the fish have fins and scales? (A must.) Are the bamboo Sukkoth covers strung together with cotton string or synthetic fibres? (Only material that grows in the ground is permissible.) Is the yak milk stored in containers that might have previously held meat? (A big no-no.)
If a mashgiah deems that the exacting standards have been met, then off to the four corners of the globe go the rice crackers, canned berries, dehydrated vegetables, frozen fruits, chocolate, tea, cooking oils, pharmaceuticals, dietary supplements, preservatives, garlic, food additives and coloring, and sundry other products. And, lo, it has come to pass that China is now the fastest-growing exporter of kosher goods on earth. And, verily, every party involved—the kosher-certifying agencies, the factory owners, the Chinese government, and the consumer--doth benefit, for I say unto you that the value of the worldwide kosher market has been estimated to be a hundred and sixty-five billion dollars per year.
Some of the inspectors work for the Orthodox Union, the largest kosher-certifying agency in the world. If you look carefully, you can see the little "O" with a "U" inside that is printed on every container of Haagen-Dazs ice cream and five hundred thousand other products. That is the Orthodox Union's hechsher (seal of approval). The first product to receive it was Heinz vegetarian beans, in 1923.
There is an abundance of earnest rabbinical discussion about what is permissible under kashruth: Is it O.K. to use toothpaste that does not have a hechsher? What is the kosher status of water buffalo? Can dishwashers be made usable for Passover by changing the racks? Despite such issues, the basic rules, as laid down in the Torah, are (arguably) straightforward. They include proscriptions against eating meat and dairy at the same meal, consuming bug-infested fruit or vegetables (though there are those who give grasshoppers and crickets a pass), and partaking of the flesh from a beast of the earth unless it has cloven hooves and chews its cud. Were these laws designed to keep Jews (a) healthy, (b) holy, (c) isolated, (d) fat, or (e) all of the above? Savants have opined at great length about these matters, and they agree on only one thing: the answer is not (e).
This business of certification is a mostly twentieth-century phenomenon. In the old days, we did not need anyone to tell us if our chicken was kosher, because we slaughtered it ourselves. We made sure that, as Deuteronomy more or less instructs, our supper was done in by a knife that had no nicks, with a quick, deep stroke across the throat which severed the carotid arteries, jugular veins, vagus nerve, trachea, and esophagus, at a point no higher than the epiglottis and no lower than where the cilia begin on the trachea. After that, we made sure that all its blood was drained within seventy-two hours.
That all seems quite straightforward but not something one wants to do every day. Nowadays, though, we can just look out for the little U in a circle and know that it's been done for us.