Kashrus in the Kitchen. The Jewish Kitchen (92)
Unsupervised Gentile in a Jewish Home. Previously, we discussed leaving an unsupervised gentile in a Jewish house. He or she might create a kashrus issue by cooking, swapping foods, or drinking a Jew’s wine. We mentioned one solution of creating an environment where the gentile is afraid to do any of the above because he might get caught by a Yid. A second solution is providing the gentile with enough available food and utensils so he would have no motivation or need to do the wrong thing. Let us discuss a third solution: making it almost impossible to do any harm without it becoming apparent because of the tamper proof restrictions. Here are a number of methods:
Tvias Ayin. If a person has unpackaged meat or fish, he can carefully look a few times at the surface layout and be able to recognize if they have not been moved around in any way.
Simanim. If one can make on the top piece(s) a slight nick with a fork that no one else would even notice, that would count as a Siman - a visible proof that this is the unchanged piece.
Sealing. If something is wrapped in a sealed package that cannot be opened without it being known, that is equivalent (or maybe better) to the double-seal required by halacha to take away the worry that a gentile might switch meats or fish. B’dieved even one seal will suffice. A person can make his own seal by taping something down in a way that he can tell the surface under the tape is still intact and not changed by someone who might have tampered with it. This can also be used to make sure that the gentile did not use any plug-in cooking item, like a microwave oven. He could unplug the item and put a fragile plastic sandwich bag around the plug and tape it over in a way that he could tell if it was tampered with. Two such taped bags would be called two seals. It should be stressed again, as was explained last week, that there is only a problem if the gentile has what to gain by doing the wrong thing. Bringing his own fish or meat to swap with a Jew’s food is not an activity that gives him any gain. However, since the Pri Toar (1) holds that this only suffices b’dieved; l’chatchila we don’t rely on this (2) and we try to secure the situation to avoid swapping. One could also tape the controls or openings of cooking items that cannot be unplugged.
(1) פרי תואר יו"ד קי"ח (2) פרי חדש שם חולק על זה