(1) 1. One who sorts food from refuse, or if there were two food types placed in front of him and he sorts one from the other - with the aid of a sifter or strainer he is chayav (liable); with a cone or dish he is patur (not liable) but it is forbidden to do so, but if he sorts it with his hand in order to eat it immediately it is permitted. RAMA Whatever one separates for a meal he is immediately about to eat, is called “for immediate use” (Heb. לאלתר). [Hamagid; the R"i; Beis Yosef; Tur; the Rosh] Even when others are eating with him it is permitted. [Tosefos] Therefore it is permitted to separate the (good) leaves of a vegetable called lettuce from the moldy ones that one requires for the upcoming meal. [Beis Yosef Siman 321]

(2) 2. One who sorts food from waste by hand for later use, even for later on that day, is as if one is sorting for storage, and is chayav.

(3) 3. Two foods that are mixed may be sorted from each other and one may place (the other food in order) to eat immediately. RAMA: Two kinds of fish are categorized as two types of food and one is therefore forbidden to sort one from the other unless done by hand to eat right away. This is even if the pieces are large and each one is noticeable by itself. If however the pieces are all one type even if one sorts the big pieces from the small it is not called sorting. Even when two types are mixed and one sorts both together the big from the small or vice versa it is permitted because one is not sorting one type from another. [Terumas Hadeshen]. If one sorted and left it for later, even for that same day, for example in the morning in order to eat in the afternoon, one is chayav.

(4) 4. One who separates waste from food even with one hand is liable. RAMA: Even if there is more food (than waste) and it is more arduous to remove the food, nevertheless one must not remove the waste even if eating is imminent. (Beis Yosef).

The Sages taught in a baraita with regard to the laws of selecting: If there were types of food before him, and he wants to remove one or more from the mixture, one selects and eats, selects and puts aside. And one may not select, and if one did select, he is liable to bring a sin-offering.

(10) 10. Clear wine and water may be filtered through a strainer RAMA: even if there are thin slivers of wood because it is drinkable as it is (Sma"g)