Question: If one is served a vegetable salad containing onions and one does not care for onions, may one remove the onions and place them in a different vessel? Similarly, if a child is served a dish containing something he does not like, may the child’s mother remove the food her child does not like from the child’s plate?
Answer: In previous Halachot, we have discussed the forbidden work of selecting on Shabbat. We have also mentioned that selecting on Shabbat is only permissible when three conditions are met: One must select by hand and not through the use of a utensil (such as a strainer), one must select the food from the waste and not the opposite, and one must select in order to eat the food immediately (and not leave it for a later time).
We have already established that regarding the forbidden work of selecting on Shabbat, there need not be a mixture of actual “food” and “waste”; rather, anything one does not desire at the present time is considered “waste” with respect to the other items. Thus, if one has apples and oranges in a bowl before him and he desires only the oranges, he may not remove the apples from the bowl for this is considered selecting “waste” from “food.”
Similarly, if one was served a vegetable salad which contains pieces of onions, which one does not like, one may not remove the pieces of onion from the salad and continue to eat, since one is selecting “waste” from “food.” Rather, one should merely eat the other vegetables and leave over the onions.
Likewise, if a child is served a dish such as rice and beans and the he does not like beans, the beans may not be removed from the rice on his behalf since they are considered “waste” with regards to him.
Nevertheless, there is a manner in which one may act leniently in this situation and that is if the child’s mother or father are interested in eating the beans, for in this case, the beans are considered “food” with regards to them and they may therefore remove the beans from the rice and eat them.
Similarly, Maran zt”l writes that if one is eating a salad which contains onions and he himself does not like onions but his friend does, one may indeed remove all of the onions for the friend who wishes to eat them and this does not constitute the forbidden work of selecting.