Too many people have difficulty believing that produce presents a problem. Enter a recent op-ed piece in the NY Times appetizingly titled, "The Maggots in Your Mushrooms." It's a must-read for any kosher consumer, simply for it's gargantuan gross-out factor. (Are you enjoying the alliteration in this post? I'm trying.) My favorite segment:
So, if you didn't believe the rabbis, believe the FDA. And if you're wondering: how is it that there can be kosher canned mushrooms? Wash them. And what about the sauerkraut? The kashrut organization checks the batches of cabbage to insure that the lot isn't infected - so they can rely on the halachic principle of "rov" - an assumed majority - for your particular hot dog. And what about the insect pieces in the peanut butter? Sorry - there you're out of luck. Only whole bugs are really, completely treif. Bug pieces, do not present a kashrut problem. Since they are so small and not an actual organism but only a part of one, they become halachically batel (nullified) in the butter.
Tomato juice, for example, may average “10 or more fly eggs per 100 grams [the equivalent of a small juice glass] or five or more fly eggs and one or more maggots.” Tomato paste and other pizza sauces are allowed a denser infestation — 30 or more fly eggs per 100 grams or 15 or more fly eggs and one or more maggots per 100 grams.
Canned mushrooms may have “over 20 or more maggots of any size per 100 grams of drained mushrooms and proportionate liquid” or “five or more maggots two millimeters or longer per 100 grams of drained mushrooms and proportionate liquid” or an “average of 75 mites” before provoking action by the F.D.A.The sauerkraut on your hot dog may average up to 50 thrips. And when washing down those tiny, slender, winged bugs with a sip of beer, you might consider that just 10 grams of hops could have as many as 2,500 plant lice. Yum.
So the peanut butter and jelly sandwich you sent in your daughter's lunch? Kosher - but not necessarily bug free. Be'tayavon!