Possibility of buying treyf meat in a kosher store

Question

Since meat may be sold to a consumer before kashering and traiboring, it is possible that parts of meat obtained from a kosher store may not be kosher.* Ordinarily, one could guess whether the meat has been kashered/traibored according to the state in which it is sold. (That is, one assumes that a whole, fresh animal carcass is presumably not kashered/traibored, whereas a butchered cut probably is.)

However, since there is the flexibility to sell both kinds of meat in the store, does this mean we cannot assume, say, that a package labeled "beef fat" contains meat free of chailev?

*(Not theoretically, abstractly possible--but literally, by definition.)

Answer 1

I don't really know what the situation in other countries in, but for a very long time, the only meat sold in stores in America has been soaked and salted. Even if a kosher-labelled piece of meat has not been salted properly, it's בטל ברוב, as the overwhelming majority of meat is completely kosher.

...you used the word "treyf," by which you probably meant the colloquial sense of "not salted." If you meant to say that the animal was technically "treyf," or not kosher due to some physical problem (certain kinds of broken leg, tear in the lung etc.), we'd also assume that it's probably fine, because every animal that leaves a slaughterhouse in America has been checked (quickly, but checked), and if something is missed, then it's also בטל ברוב.

However, there are some really treyf pieces of meat that get through to the consumer. Most of the time you won't be able to tell, however, and can thus rely on the ביטול ברוב. All the same, there are certain problems that you can recognize in your store-bought chicken. The ones that you can find in poultry have been described by Rabbi Yisroel Belsky in an octapartite video series (named, aptly, "What's Wrong with this Chicken?" ;) that you can buy from the OU. (I haven't checked, but I'm fairly certain that these videos can be found on Youtube as well. Search for "Belsky what's wrong with this chicken")

(I threw out a chicken leg last night for having a problematic bruise, the kind of which was described in those videos. It's rare, but it happens...and most people don't realize it.)