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One of the melachot in the process of preparing bread is Losh. The primary example of this melacha is kneading flour and water together to make dough.


  1. The three criteria necessary in order to violate the biblical prohibition of Losh are:
    1. there is a mixture of two ingredients,
    2. one of the ingredients is powdery like flour, chopped (like chopped eggs), or thick (like jam), and
    3. the mixture forms a thick dough-like substance [1]
  2. It’s forbidden to mix two ingredients when they combine either (1) because one of them is a liquid, (2) there is liquid naturally present in one of the ingredients (such as a fruit), or (3) one of the ingredients is a thick coagulating substance (such as mayonnaise). [2]
    1. If there is no liquid added and there’s no way that the ingredients will fuse it’s permitted to mix the ingredients. For example, it's permissible to mix sugar and cocoa powder or cinnamon. [3]
    2. It's permissible to pour honey on whole nuts.[4]
    3. One may pour gravy on rice and mix it.[5]
  3. Kneading flour and water is a violation of the biblical prohibition of Losh (kneading).[6]

Combining the Ingredients

  1. Just as it is forbidden to knead two ingredients together so too it is forbidden to pour one onto the other so that they will mix automatically. Therefore it is forbidden to pour water onto flour or flour onto water on Shabbat.[7]

Bar Gibul

  1. There is a distinction between something which is bar gibul, meaning mixed easily and something which is lav bar gibul which doesn't mix easily.[8]

a Mixture Which Was Mixed Before Shabbat

  1. Even if the two ingredients were poured one upon another before Shabbat it is forbidden to knead them together on Shabbat.[9]
  2. If two ingredients were kneaded together before Shabbat, it is permissible to add liquid and even mix slowly.[10]
  3. Therefore, if oil separated from peanut butter and floats on top of it, it's permissible to remix it. It would even be permissible to add more liquids. Adding more solids, however, is forbidden.[11]

Making a thin mixture

What is a thin mixture?

  1. Ashkenazim hold that anything which pours from one vessel to another is considered a thin mixture. [12] Sephardim hold that even if it pours from vessel to vessel it’s not considered a liquid unless it is drinkable and not just meant for eating. [13]

When is it permissible to make a thin mixture?

  1. According to Ashkenazim, it is only permitted to mix a thin mixture if one both changes the order of putting in the ingredients and stir it in a different way. [14]
  2. According to Sephardim it’s permitted to mix a thin mixture if one either changes the order in which one puts in the ingredients or if one changes the way one mixes. [15]

What is considered a change in the order?

  1. A variation in the order means that if one normally puts the solid ingredient in first, then one should put the liquid ingredient in first, if one normally puts the liquid in first, then put the solid in first. If there is no set order then one should put the solid in first. [16]
  2. If one doesn’t know what order is the common practice one may assume that the instructions on the package is the common practice and one may reverse the order of that. [17]
  3. If there’s no clear common practice one such put the solids first and then the liquid. However, one should only use this leniency in cases of necessity. [18]
  4. If there is no liquid but only a coagulating substance (ex: mayonnaise) there is no need to change the order in combining the ingredients. [19]

What is considered a change in mixing?

  1. If possible one should stir it with one’s finger or mix it by moving the bowl. If that’s not possible one should use an instrument but mix in a criss cross manner and preferably remove the utensil after each stroke. [20] According to some poskim, mixing it with the handle of the spoon or knife is sufficient.[21]

Making a Thick Mixture

  1. Generally, it is forbidden to make a thick mixture on Shabbat and even pouring in a liquid without mixing is forbidden.[22]
  2. If one needs to prepare a thick mixture on Shabbat and one can’t make it completely before Shabbat, then one should before Shabbat mix some liquid into the solid so that all of the solid is saturated. On Shabbat one may mix in more liquid as long as this doesn’t cause the mixture to thicken and one also does the two variations above (switch order and way it’s mixed).[23]
  3. In cases of need for this food specifically, such as baby food, and it can't be made before Shabbat, it is permitted to make it with two variations, one in the pouring and one in the mixing.[24]
  4. Examples of variations in the mixing include: 1) mixing with a criss-cross and removing the spoon each time, 2) just shaking the bowl to stir the contents, or 3) mixing with one's finger and not a spoon.[25]
  5. It is permitted to make a little bit of a thick mixture on Shabbat for immediate consumption. Some say that this only applies to dry ingredients that wouldn't form a dough (lav bar gibul) such as matzah meal or roasted grain flour. The amount of what is considered a small amount must be less than what is usually done so that it is clear that this case is different than usual. It can't be more than a meals worth. Also, it must be made for immediate consumption.[26]

Making a Watery Mixture

  1. It is permitted to mix solid particles with a lot of liquid if it will result in a very watery mixture such as making baby formula from powder and water. Nonetheless, one must be careful to pour in the liquid at once and not gradually. [27]

Cooked Foods

  1. Many poskim hold that there is no prohibition of losh to add liquids into cooked foods. Therefore, one may mix margarine into mashed potatoes.[28]
  2. It is permitted to mix cinnamon or raisins into a cooked cereal such as oatmeal.[29]
  3. Some say that it is permitted to mix a little amount of liquid with instant coffee or sugar and mix it gently.[30]

Practical Examples

Mashing a Banana

  1. It's permissible to mash a banana with the handle of a fork or spoon.[31]
  2. However it is forbidden to add any liquid to such a mixture.[32]

Making Vegetable Salad

  1. The prohibition of kneading does not apply to large chunks of food which will be distinct even after being mixed. [33]
    1. For example, one may dress a salad (with oil, vinegar, mayonnaise, and seasoning) if the vegetables are slightly large pieces. [34]

Making Egg Salad, Tuna Salad, or Potato Salad

  1. To avoid all issues it’s preferable to make egg salad, tuna salad, potato salad, or salads with vegetables and mayonnaise before Shabbat. However, if one didn’t, one may do so on Shabbat in the following manner:[35]
    1. Step 1: Peeling and Mashing Eggs: One may peel the eggs right before the meal and then mash them even with the prongs of a fork.[36]
    2. Step 2: Peeling and Cutting Onions: The onions should be peeled right before the meal and cut in slightly large pieces.[37]
    3. Step 3: Mashing the Potatoes: One can mix in the cooked potatoes using the handle of a fork, or if the potatoes are very soft because of the cooking one may mix it with the prongs of the fork. [38]
    4. Step 4: Pouring in Ingredients: one should first put in the mayonnaise and then the salad since that is different than the way one would do it during the week.[39] Some say that it isn't necessary to make a shinuy in the pouring.[40]
    5. Step 5: Mixing Ingredients: One should mix with a shinuy such as criss-cross and not in a circle.[41]
    6. Removing Egg Shells: If an egg shell got mixed into the salad one may only remove it together with a bit of other food, but preferably one shouldn’t remove the egg shell but just eat around it. [42] See Borer.

Instant Mashed Potatoes

  1. One may not make instant mashed potatoes as it is considered a thick mixture. [43]

Instant Pudding

  1. One may not make instant pudding as it is considered a thick mixture. [44]


  1. One shouldn't make Jello on Shabbat since it becomes a thick mixture.[45]


  1. According to Ashkenazim, one may not make thick mayonnaise on Shabbat and thin mayonnaise preferably should be made before Shabbat.[46] According to Sephardim one may make mayonnaise on Shabbat if one is doing so in order to eat it immediately. That is, it is permitted to mix eggs, oil, mustard, sugar, and some salt. Also, one shouldn't mix them vigorously.[47]


  1. When one substance becomes completely absorbed into the other so that there isn't a noticeable difference in the consistency of the liquid, there is no problem of lisha. For example, one may add instant coffee or hot cocoa to a cup of hot water (as long as there is no problem of bishul).[48]


  1. If one wants to have guacamole on Shabbat and it wouldn't be fresh if made in advance one should mash the avocado with the handle of the spoon or the like. To add in onions, tomatoes, lemon juice, or spices and avoid the issue of losh, one would have to use a double shinui. That is, one should put in the lemon juice or spices first and then the avocado and mix it with the back of a spoon or with a criss-cross action.[49]


  1. One should not put a lot of granola in yogurt so that it becomes a thick mixture. One may put in a few so that it is a thin mixture as long as one changes on how it is put in and mixed. That is, one should first put the granola and then the yogurt and also one should mix it with a criss-cross.[50]

Other Examples

  1. It is forbidden to pour water on sand. Therefore, children playing in a sandbox should not pour water into it.[51]
  2. If one needs to wash his hands or urinate on the ground, he should look for an area without any loose sand or dirt. In a case of an extenuating circumstance one may be lenient.[52]



  1. Shemirat Shabbat KeHilchata 8:1
  2. Shemirat Shabbat KeHilchata 8:1, Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 143)
  3. Shemirat Shabbat KeHilchata 8:4 explains that since the ingredients don't stick together into one dough. Chut HaSheni (vol 1 pg 105) agrees.
  4. Shemirat Shabbat KeHilchata 8:4 explains that since the ingredients don't stick together into one dough.
  5. Shemirat Shabbat KeHilchata (in new editions 8:24)
  6. As is evident from gemara Shabbat (18a), mixing flour and water is a violation of Losh (Menuchat Ahava 9:1). Chut HaSheni (Shabbat vol 1 pg 105) defines Losh as the prohibition to mix two ingredients using a liquid to form a dough.
  7. In Gemara Shabbat 18a there is a dispute whether one is liable for violating Losh by simply pouring liquid into flour or only if one both pours in the water and mixes it. The majority of the Rishonim (Rif, Rambam, Rosh, Ramban, and Ran, cited by Shaar haTziyun 321:57) hold that one isn't biblically liable until one has both poured in water and mixed it into dough (Mishna Brurah 321:50), nonetheless, Mishna Brurah 321:57 (quoting the Magen Avraham) there is a rabbinic prohibition even for just pouring liquid into flour or the opposite. This is also the ruling of Shemirat Shabbat KeHilchata 8:5, 39 Melachos (by Rabbi Ribiat, vol 1, pg 531), and Menuchat Ahava 9:1.
  8. The gemara Shabos 155b distinguishes between what is known as a Bar Gibul as opposed to a Lav Bar Gibul. The basic distinction between the two is that a bar gibul is something which mixes easily upon addition of liquid, such as fine powder, flour, or sand, while a lav bar gibul is something that does not.
    • However, within the very definition of a lav bar gibul, there is a machlokes as to what its halachic status is. Rambam Shabbos 8:16 suggests that because these substances, such as ash or coarse sand never truly fuse with the substance it is being mixed with even when water is added and kneading is done, it is therefore not subject to the melacha altogether. Nonetheless, the Rambam (Shabbos 21:34) writes that would be a rabbinic concern of appearing as lishah. Mishnah Brurah 321:50 quotes this.
      Most poskim (Tosfos, Rosh, Rashba, Raavad, and Ran cited by Shaar hatziyun 321:60) however, understand that a lav bar gibul is still subject to the melacha of losh, and therefore in certain circumstances may be dealt with in an even more stringent manner than a bar gibul material, for it would be culpable simply upon addition of water, without any kneading, considering that the kneading does not accomplish anything of significance.
  9. Shemirat Shabbat KeHilchata 8:6 based on Beiur Halacha 321:15 s.v. Ein
  10. Shulchan Aruch O.C. 321:15, Mishna Brurah 321:58, Shemirat Shabbat KeHilchata 8:7
  11. Shemirat Shabbat KeHilchata 8:7
  12. Shemirat Shabbat KeHilchata 8:8
  13. Menuchat Ahava (vol 2, 9:12, pg 301)
  14. Shemirat Shabbat KeHilchata 8:9
  15. Menuchat Ahava (vol 2, 9:10-11, pg 298-300)
  16. Shemirat Shabbat KeHilchata 8:9
  17. Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 150) quoting Rav Shienburg
  18. Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 150)
  19. Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 151)
  20. Shemirat Shabbat KeHilchata 8:9
  21. Sh"t Igrot Moshe 4:74 (Losh #6, in some editions #11), 39 Melachos (Rabbi Ribiat, vol 1, pg 545). Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 153) agrees and adds that this isn't sufficient for a thick mixture.
  22. Hilchot Shabbat Bshabbat 13:23 p. 713 based on Sefer Hatrumah cited in Shulchan Aruch 321:16
  23. Shemirat Shabbat KeHilchata 8:10
  24. Shemirat Shabbat KeHilchata 8:11 based on Mishna Brurah 321:68 regarding charoset. For Sephardim see Kaf Hachaim 321:90-91, 113 and Yalkut Yosef v. 3 Tikkunei Maachal n. 31 fnt. 41.
  25. Hilchot Shabbat Bshabbat v. 1 13:23 p. 713
  26. Shulchan Aruch O.C. 321:14, Hilchot Shabbat Bshabbat v. 1 13:24 p. 714
  27. Shemirat Shabbat KeHilchata (in new edition 8:29), Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 147), Menuchat Ahava (vol 2, 9:13, pg 302)
  28. Shulchan Aruch O.C. 321:19 rules based on the Rambam (responsa 109) that one may stir a dish of grits and meat and mash them so that they dissolve and form into one mass. Bach 321 questions the Rambam and says that one may only stir gently. Magen Avraham 321:28 agrees. However, the Taz 321:14 writes that since the meat and grits have been mixed with water and cooked before shabbos, there is no problem of losh in mixing it again. Chazon Ish 58:9 agrees if there is some liquid there from before Shabbos, one may then put in more on Shabbos. Biur Halacha 321:14 s.v. shema adds another reason to be lenient with stirring food that is already cooked; since it is already fit for eating, the kneading becomes part of the process preparing it for eating, derech achila, and would be permitted if you stirred a little bit at a time. Mishna Brura 321:77 advises following the strict views of the Bach and Magen Avraham. Chazon Ish 58:9 allows stirring even vigorously. 39 Melachos (pg. 540) writes that you can mix margarine, butter, or oil into a baked carrots or mashed potatoes. Shemirat Shabbos Kehilchata 8:24 agrees.
  29. Shemirat Shabbos Kehilchata 8:25 cites Rav Shlomo Zalman Auerbach who based on Biur Halacha 314:21 s.v. shema's first answer thinks that there's no biblical losh on cooked foods permits even adding cinnamon or raisins into cooked oatmeal cereal. However, in the footnote he adds that raisins in cooked cereal doesn't become a dough unit and isn't losh at all.
  30. Menuchat Ahava (vol 2, 9:20, pg 308) based on the fact that the powders are precooked.
  31. Shemirat Shabbat KeHilchata 8:3 writes that it's permissible in terms of Losh even though it sticks together because it is not composed of two ingredients. Nonetheless due to a concern of Tochen one must use the handle of a fork or spoon. A similar analysis is found in Sh"t Igrot Moshe 4:74 (Losh #2 at the end) and Chazon Ish (OC 58:9 s.v. Yesh).
  32. Shemirat Shabbat KeHilchata 8:3
  33. Shemirat Shabbat KeHilchata 8:4, Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 143)
  34. Shemirat Shabbat KeHilchata 8:4 explains that since the ingredients don't stick together into one dough. Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 143) agrees.
  35. Shemirat Shabbat Kehilchata 8:28
  36. Shemirat Shabbat Kehilchata 8:28
  37. Shemirat Shabbat Kehilchata 8:28
  38. Shemirat Shabbat KeHilchata 8:28
  39. Or Letzion 2:33:3 writes that when making salad with mayonnaise one should first put in the mayonnaise and then the salad since that is different than the way one would do it during the week. Also, one should mix with a shinuy such as criss cross and not in a circle. Dor Hamelaktim v. 5 p. 2962 quotes Rav Moshe Feinstein (Mesoret Moshe v. 3 n. 208) as agreeing. Shemirat Shabbat Kehilchata 8:20 and 8:28 agrees that one can make egg or tuna salad with two shinuys though it is better to do it before Shabbat. He also notes the more lenient opinion regarding egg salad. Rabbi Langer (Chicago Kollel Devarim 5769) quotes and explains the Shemirat Shabbat Kehilchata 8:28 and extends it to egg salad with mayonnaise and not just eggs, onions, and oil that Shemirat Shabbat was discussing.
  40. Orchot Shabbat 1:6:18 cites the Shevitat Hashabbat (Intro to Losh n. 6) who limits losh to water or liquids that permeate the solids to consolidate them and it wouldn't apply to thick fatty liquids such as mayonnaise. Orchot Shabbat is willing to rely on this opinion with respect to pour the ingredients together since anyway we really hold like the opinion that losh is violating by kneading and not pouring (Rabbi Yosi Bar Yehuda). He concludes that Rav Shlomo Zalman Auerbach liked this approach. Dor Hamelaktim v. 5 p. 2961 cites Shabbos Kitchen p. 161 who holds that one should make it in advance but in a case of need it could be made with a shinui in the mixing. Rabbi Yakov Goldstein on shulchanaruchharov.com agrees.
  41. Shemirat Shabbat Kehilchata 8:28, Orchot Shabbat 6:18. Shemirat Shabbat Kehilchata notes that the minhag is to mix in oil without any variations, however, it’s proper to make above variations (in order of putting in ingredients and way of mixing).
  42. Shemirat Shabbat KeHilchata 8:28
  43. Shemirat Shabbat KeHilchata (in new editions 8:29), Menuchat Ahava (vol 2, 9:15, pg 304), Practical Laws of Shabbat (Rabbi Rafael Soae, vol 2, pg 111), Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 164), See Igrot Moshe 4:74 (Losh #7)
  44. Shemirat Shabbat KeHilchata (in new editions 8:29), Menuchat Ahava (vol 2, 9:15, pg 304), Shabbos Kitchen (Rabbi Simcha Cohen, chap 11, pg 164), See Igrot Moshe 4:74 (Losh #7)
  45. Benetivot Hahalacha v. 37 p. 289 citing Shevet Halevi 7:41 and Chut Shani p. 114
  46. Shemirat Shabbat KeHilchata (in new edition 11:33)
  47. Yalkut Yosef 321:31, Yalkut Yosef English 321:26, Leviyat Chen 67
  48. Chazon Ish 58:9, Sh”t Iggerot Moshe OC 4:74: Losh 1, Shemirat Shabbat Kehilchita 8:29
  49. Or Letzion 2:33:5, Rav Daniel Mann. Orchot Shabbat 6:15:1 clarifies that even when discussing a belili avah we hold that if it would spoil if it was made before Shabbat it is permitted to be made on Shabbat. Nonetheless, one must use a shinuy in the mixing and it is preferable to make a shinuy in the order of how the ingredients are put in.
  50. Benitvot Hahalacha v. 37 p. 289
  51. Rambam (Shabbos 8:16) based on the Gemara Shabbos 18a writes that kneading water and dirt is forbidden from the torah as a tolada of losh. Based on that, Shemirat Shabbos KeHilchata 16:4, Children in Halacha (Rabbi Simcha Bunim, pg 137-8), and 39 Melachos (Rabbi Ribiat, vol 2: pg 253-254) write that children who are playing in a sandbox may not pour water into it.
    The Gemara (155b) cites a dispute as to when one would have violated losh. According to Rebbi, pouring water into flour is enough, while according to Rabbi Yosi bar Yehuda, one isn’t liable until he kneads them together to form dough. The Rif (67b), the Rambam (21:34) and the Rosh (24:3) rule like R’ Yosi bar Yehuda that it is only forbidden midirabanan to pour water without mixing it, while the Yereim (Ch. 274, 133b), the Teruma (Ch. 220), the Semag (Prohibition 65, lash) and the Semak (Ch. 280) hold like Rebbe. The primary opinion of Shulchan Aruch O.C. 321:16 is like R’ Yosi, however, he also cites the opinion of Rebbi. Chacham Ovadia Yosef (Livyat Chen 67) and Menuchat Ahava 2:9:9 are lenient. Rama is strict and this view is accepted by the Ben Ish Chai (Mishpatim 18) and Kaf Hachayim (324:14).
  52. The Mishna Brurah 321:57 cites the Magen Avraham that it is forbidden to urinate on mud because of losh and the same would be true of loose dirt or sand, even though it is unintended. He also cites the Beit Meir who is lenient in a case of need, to urinate even upon mud since he rules like Rabbi Yosi Bar Yehuda (cited in Gemara Shabbat 155b) that it is only derabanan if you don't mix but merely pour water. Mishna Brurah concludes that one may be lenient in case of need when the mud doesn’t belong to you, since one doesn’t benefit from the dirt mixing with the liquid. Kitzur Shulchan Aruch 80:14 and Menuchat Ahava 2:9:2 p. 287 agree that if possible one should be careful. See also Ketzot Hashulchan 130:8.
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