Crushed, Minced Fruits or Vegetables
17. The poskim discuss whether the issur of losh also applies to mixing liquid with completely crushed or very finely minced fruits or vegetables, as the liquid does not combine the pieces into a single mass. Also, it is not similar to ash, which is subject to the issur of losh even though it is not combinable with water (Issue 349, par. 9), as ash does gather and collect well, as opposed to small pieces of fruits and vegetables.
18. Some hold the melacha of losh does not apply because the liquid does not combine the pieces into a single mass (יראים, או''ז סי' ס''א, תוס' רי''ד הובא בריא''ז בשלטי גיבורים ).
19. However, others hold the melacha of losh applies to fully crushed fruits and vegetables. Thus, they may only be prepared with a shinui in the mixing, which, strictly speaking, is enough (תרומת הדשן סי' נ''ג, ב''י סי' שכ''א, שו''ע שם סט''ו וט''ז ). According to the machmir opinion that adding the liquid alone is an issur d’oraisa, it should not be made at all as a thick mixture on Shabbos (ספר התרומה, י''א בשו''ע הנ''ל ), unless it cannot be prepared before Shabbos; it is for baby food; or it is done by a non-Jew (Issue 349, par. 32 and on).
Various Salads
20. Because of this, salads that will not go bad if prepared Erev Shabbos may not be prepared on Shabbos due to the issur of losh. Some salads may be prepared if they are mixed with a shinui.
21. Eggplant salad. Eggplant salad made from crushed eggplant mixed with vinegar, oil, and mayonnaise should not be made on Shabbos, as it is a thick mixture and will not go bad if it is made Erev Shabbos. However, if one only uses mayonnaise [which is thick and not subject to the issur of adding the liquid (Issue 349, par. 28)] but no other liquids, he may make it on Shabbos if he mixes it with a shinui, e.g., with a crisscross motion (ארחות שבת פ''ו אות ל' ).
22. Coleslaw. A salad made from chopped cabbage and carrot mixed with mayonnaise and vinegar does not usually have small enough pieces to be a problem of losh. Thus, one may make it on Shabbos. However, if the pieces are totally ground up and it is like porridge, it must be mixed with a shinui if it is made on Shabbos.
23. Vegetable salad. One may mix oil into a vegetable, lettuce or potato salad on Shabbos. There is no issur of losh since the pieces are not so finely chopped.
24. Fruit salad. Similarly, one may mix orange or lemon juice into a fruit salad without any issue of losh since the fruits are not so finely cut.
25. Tuna with mayonnaise. Mixing canned tuna with mayonnaise has the same halachos as making egg salad (Issue 350, par. 43). The mayonnaise does not need to be put in with a shinui since it does not seep into and get mixed with the tuna on its own. With respect to the mixing, strictly speaking one may rely on the majority opinion that there is no problem of losh; one who wants to be machmir can mix with a shinui, e.g., with a crisscross motion.
