Q. With a large family and a moderate size sink, we need the Friday night Shabbat dishes out of the sink after the meal, so we pack them into the dishwasher. (Usually we will not need these plates again on shabbat.) The problem is that if they are not rinsed off fairly well, then the dishwasher will not clean them properly and perhaps it can lead to problems with the dishwasher. It would seem that rinsing them off before putting them into the dishwasher is "preparing for the weekday", so I'm wondering what I can do. 1) Running them under the water briefly will remove some of it, but often doesn't remove enough of the food stuff. 2) if I move the plate around under the stream of water so that the stream of water hits the spots where the food is, that direct water pressure will usually take off enough of the leftovers. 3) For more stubborn pieces of leftovers, a quick & light scrub with my thumb would do the job. Are any of these permissible or do we need to place them into the dishwasher dirty and then remove them all after Shabbat to properly rinse them, then put them back in to be cleaned (which we would rather not do, as there is already so much cleanup after Shabbat!)
A. See question 968 in regards to storing used dirty dishes in the dishwasher to keep the kitchen clean during Shabbos (if no light goes on or off). We wrote; Poskim permit storing dirty dishes or soiled clothing in a washing machine if the purpose is to keep clean the house and not to prepare or set up to save time after Shabbos. (Igrois Moishe 4: – 39 Melochos p. 115 et. al.).
Mishne Halochos (4: 43 and 4:44) explains that there is no ma’aras ayin prohibition involved by placing oneself in a situation where an onlooker may suspect that one is about to wash the dishes or the clothing on Shabbos, if customarily during the weekdays one also stores away the dishes and washes them at a later time, when the machine becomes full.
Horav Shlomo Miller also advises not to place on Shabbos the dishes each one orderly and separately inside the racks, ready to be washed, but rather to just pile them up and get them out of sight.
On question 306- 307 regarding lightly soaking soiled dishes with cold water after meals on Shabbos, we wrote: It is forbidden to prepare on Shabbos for the weekdays even on arrangements that do not qualify as melochos by themselves, and involve only slight effort such as soaking dishes or fetching wine (Mishna Berura 503: 1).
However when there is a likely possibility that they will be still needed during Shabbos, even after Seudo Shlishis (ibid. 323: 28), or they create a foul odor or will attract insects, they could be soaked in cold water as needed.(Sh’miras Shabbos Kehilchoso 12: 2). The Rov's opinion is that it is also permitted to add liquid soap to the water when needed now to avoid foul odors or attracting insects.
In regards to scrubbing on question1512 we wrote: The prohibited melacha of melaben or cleaning usually applies to materials that absorb liquids such as fabrics and clothes. Washing dishes, pots and pans is permitted in cold water, when needed for that Shabbos. (O.H. 323: 6, in regards to leather shoes). It is permitted to rub and remove from a dry plastic tablecloth a dry stain with a dry cloth. (similar to O.H. 302: 6, Mishna Berura ibid. 26), but no wet cloth, napkins or paper towels should be used; neither should they be used to collect or clean spilled liquids, as you will come to squeeze the wet materials. You may however use a rubber squeegee or non absorbent material to remove or push aside spilled liquids from the plastic or water spilled for cleaning purposes. However, vigorous rubbing or shifshuf should preferable be avoided. See Shemiras Shabbos Kehilchoso (12: 41). See also Igrois Moshe (Y.D. 2: 79).
Horav Shlomo Miller's Shlit'a opinion is that there is basically no difference in the various kinds of plastic tablecloths in regards to the above question or between the different communities who use them.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit'a