one desires the raisins and dislikes the peanuts: Removing (effectively sorting) the peanuts from the bowl, leaving a 'purified' pile of raisins free from unwanted peanuts, would be sorting/purification as the peanuts are removed. However, removing the desirable raisins from the peanuts does not purify the mixture, as one is left with undesirable peanuts (hence unrefined) not a refined component as before, and is thus permissible. Note that in this case there has not been any extraction of material from either the peanuts or raisins (threshing/extraction), just the sorting of undesirable from desirable (sorting/purification). General Introduction: After threshing, a mixed collection of waste matter remained on the threshing floor together with the grain kernels. Included in this combination would be small pebbles and similar debris. These pebbles could not be separated by winnowing because they were too heavy to be carried by the wind. The pebbles and debris were therefore sorted and removed by hand. This process is sorting/purification. Any form of selecting from (or sorting of) an assorted mixture or combination can be borer. This includes removing undesired objects, or matter from a mixture or combination. Borer with mixed foods: Even though the classic form of borer as performed in the Mishkan involved the removal of pebbles and similar waste matter from the grain produce, sorting/purification is by no means limited to the removal of "useless" matter from food. In fact, any selective removal from a mixture can, indeed, be sorting/purification, even if the mixture contains an assortment of foods. The criteria are types and desire, not intrinsic value. Therefore, removing any food or item from a mix of different types of foods simply because he does not desire the item at that time is considered sorting/purification. The three conditions of sorting/purification: Sorting/purification is permitted when three conditions are fulfilled simultaneously. It is absolutely imperative that all three conditions be present while sorting/purifying B'yad (By hand): The selection must be done by hand and not a utensil that aids in the selection. Oḥel Mitoḥ Psolet (Good from the bad): The desired objects must be selected from the undesired, and not the reverse. Miyad (Immediate use): The selection must be done immediately before the time of use and not for later use. There is no precise amount of time indicated by the concept of "immediate use" (miyad). The criteria used to define "immediate use" relate to the circumstances. For instance