Nowadays, Jews in America and Europe often rely on national or regional hechsherim whereby a product is certified as kosher by a rabbi the consumer does not know (and may not even really know who the mashgiach or rabbi is). This seems to me a relatively modern phenomenon. The gemara and early poskim discuss certain cases where we know a specific food item is kosher based on simanim or the concept of a seal as an indication against tampering (e.g., in the chanukah story). But is there early precedent for the concept of an organization or rabbinate vouching for a product or establishment and, especially, sending that product to other locales or throughout a large area who will also rely on the hechsher?
When did the paradigm of modern hechsherim like the OU, star K, etc. first arise? And when they did, was the concept at all controversial? For example, I could imagine objecting that a written symbol doesn't fall within the category of "ed echad" or that an occasional mashgiach can't really be certain everything that's being put in the soda, cookies, peanut butter, etc.
