By Horav Yosef Yeshaya Braun, member of the Badatz of Crown Heights
Question: P’soles (waste or unwanted food) may not be separated from ochel (desirable food) on Shabbos due to the issur (prohibition) of the melachah of borer (selecting). When using a keli (utensil designed for separating), ochel may not be separated from psoles either. That being the case, may a non-electrical salad spinner be used to dry lettuce on Shabbos, since it separates the lettuce, ochel, and the water, p’soles?
Answer: One of the key principles in Shulchan Aruch for determining what constitutes the act of borer which is forbidden on Shabbos, is that borer is as follows: It applies only when separating two distinct items that are mixed together, such as nuts and raisins, whereas removing an element within a particular item of food or drink that is generally considered indistinguishable, like sediment in wine or pulp in orange juice—although technically separable—is permissible.
Therefore, if there is a small amount of water left on lettuce, it’s permissible to use a salad spinner on Shabbos to get rid of the water. This is because lettuce is perfectly edible if it’s slightly wet, and most people wouldn’t mind. Drying lettuce with a salad spinner would only be considered borer to an istenis, a person who is very particular, and who absolutely couldn’t eat lettuce if it was slightly wet.
Another reason why drying lettuce is permitted is that removing moisture from lettuce is comparable to rinsing fruits and vegetables, which isn’t considered borer (for various reasons), and is permissible on Shabbos.
Although there are some contemporary authorities who are more stringent and rule against doing this, the accepted halachah is that using a salad spinner to remove moisture from lettuce on Shabbos is permissible.