Is there a problem of borer washing off fruits and vegetables? Shulchan Aruch 319:8 rules that one may not place dirty wheat in water where thereby the dirt will be separated from the wheat. The Mishna Berura says that this halacha applies also to potatoes and would seemingly apply to all fruits and vegetables. The case of the Shulchan Aruch is referring to a total mixture with the dirt getting in between the pieces of wheat. A case can be made that one apple, even covered with dirt, might not be applicable to this halacha! Indeed, this is the opinion of R’ Shlomo Zalman Aurbach who allows to wash off fruits. He says that this is called cleaning, not taking bad from the good. R’ Moshe Feinstein O”H 1-125 concurs with this opinion, but adds that it the washing should be done before the eating, and not to be put aside for later. Putting the fruit in water to separate the dirt would be forbidden being that this is considered an act of borer. It should be noted that some poskim do not draw this distinction, and forbid even washing off dirty fruit on Shabbos. All would agree, however, that clean fruit that one normally washes off for hygienic reasons can be washed without regards to the laws of borer. Furthermore, washing dirty dishes is permitted even not prior to use, even according to those that forbid washing dirty fruit.

Rabbi Tzvi Aryeh Hyman, Mir Yeshiva