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Practical Q&A May one make instant foods through mixing water and a powder together, such as instant mashed potatoes/porridge/rice?[1] All instant food powders such as mashed potato mix, and the like, which are only edible when mixed with water may not be made on Shabbos into a thick mixture. However, one may make it into a thin mixture together with the required irregularities, as defined above. [However, there are Poskim[2] which prohibit making instant potato mix even into a thin batter under the basis that they nevertheless stick to each other.]   May one make oatmeal on Shabbos? It is forbidden to make it into a thick batter even using cold water. However, one may make it into a thin mixture using an irregularity, as defined above. In all cases one may not use hot water even of a Keli Shelishi due to the cooking prohibition.[3]   May one make instant pudding or Jell-O?[4] No.[5] It is however permitted to make it very liquidly to the point it can be drunk, and will not congeal in the interim.[6]   May one make Tehina on Shabbos? Adding water to pure Tehina:[7] It is forbidden to make a normal texture of Tehina by placing water to pure Tehina, if the Tehina did not have water mixed into to it before Shabbos.[8] It is however permitted to add a large amount of water ]simultaneously-not drop by drop] to the Tehina and make it into a thin batter [i.e. a thinner mixture than usual[9]], provided one does so with the two forms of irregularities. [One is to 1) Place the ingredients together in opposite order and 2) not mix the batter in a way that is usually done with a spoon or fork.] Some Poskim[10] however rule it is permitted to make Tehina regularly on Shabbos, even if the mixture will not be thinner than usual. [Practically, one is not to make Tehina on Shabbos unless he follows the regulations mentioned above which are 1) Thinner batter than usual and 2) Place the ingredients together in opposite order and 3) Not mix the batter in a way that is usually done with a spoon or fork.] Adding more water to a Tehina dip: If water was mixed into the Tehina from before Shabbos and one now desires to make it thinner, it is allowed to be done so long as the Tehina will not thicken in the interim. Nevertheless, one may only mix the water using one’s hands rather than a spoon, or use another form of irregularity. Thickening it: If the Tehina is too liquidly, it remains forbidden [according to the main opinion above] to add any Tehina or other food to the mixture to make it thicker [unless the final batter will still be thinner than the way it is made during the week, and one uses the above two forms of irregularities].   May one make an egg salad with mayonnaise on Shabbos? Some[11] rule it is forbidden to be made on Shabbos.[12] Others[13] rule it may be done on Shabbos. Practically, one may do so using an irregularity.[14] Thus he is to first place in the mayonnaise and then the eggs, as well as he is to mix it [using his fingers or by shaking the bowl, and if this is not possible then he may] with a spoon back and forth and opposed to in a circular motion. It is preferable to remove the spoon between each time.   May one mix mayonnaise into tuna fish on Shabbos? This follows same status as egg salad in which some Poskim[15] prohibit making it on Shabbos, while others[16] rule it is permitted.   May one mix mayonnaise into eggplant to make Chatzilim? This follows the same ruling as stated above regarding egg salad in which some Poskim[17] prohibit making it on Shabbos, while others[18] rule it is permitted.   May one mix mayonnaise with tuna or eggs on Shabbos? Some[19] rule it is forbidden to be made on Shabbos.[20] Others[21] rule it may be done on Shabbos.[22] [Practically, one may do so using an irregularity.[23] Thus he is to first place in the mayonnaise and then the tuna/eggs, as well as he is to mix it [using his fingers or by shaking the bowl, and if this is not possible then he may] with a spoon back and forth and opposed to in a circular motion. It is preferable to remove the spoon between each time. The above only refers to mixing mayonnaise with small pieces of egg or tuna and hence making it into a single lump. However, if the piece of the egg or tuna are chunky, and hence do not form a single lump, it is permitted to be mixed according to all, even without an irregularity.]   May one mix mayonnaise into eggplant to make Chatzilim? This follows same status as egg salad in which some Poskim[24] prohibit making it on Shabbos, while others[25] rule it is permitted. [Practically, it is best to only do so before Shabbos.[26]]   Does mashing a banana and the like contain a kneading prohibition?[27] No –See above Halacha 1 Q&A. Nevertheless, mashing contains a grinding prohibition and may only be done in ways explained in “The laws of Grinding”-See There!   May one knead liquid into a mashed banana?[28] The Ketzos Hashulchan allows this to be done with an irregularity for the reason that doing so before Shabbos would ruin the banana, and thus in such a case one may be lenient like the first opinion mentioned above which allows kneading with an irregularity foods which are not knead-able. The Chazon Ish[29] however rules that liquid may not be added to bananas.   Q&A on mixture not defined as kneading When making a bottle for an infant from milk powder must it be made with the required irregularities?[30] If the milk powder will dissolve immediately upon adding the liquid to it, then it is allowed to be made without any irregularities[31] [although according to some doing so would involve a Nolad prohibition, and thus although one may be lenient it is proper if possible, to prepare this mixture from before Shabbos.[32]] However, if the powder will not dissolve right away and will become a semi thick mixture in the interim of it dissolving into the liquid, then it may only be made with the above-mentioned irregularities.[33] Others[34] however rule even in such a case one may do so in the normal way. Due to the cooking prohibition, one is only to use water from a Keli Shelishi, or water which is poured from a Keli Sheiyni.   When adding liquid into cocoa powder and the like must one do so with an irregularity?[35] See above Q&A.   May one mix mayonnaise/oil/honey into cut fruits/vegetables and foods of the like?[36] Cut large: The kneading prohibition only applies when the two substances are being mixed in a way that they join and stick to each other forming one entity, as is the case with dough which is a mixture of flour and water, or with cooked oatmeal. Thus, whenever solids are large enough to prevent this form of unity in their mixture, and it is rather that the liquid cotes over the solids, or that the solids are submerged within the liquids, then it is allowed. One may thus pour oil over his vegetable salad and cases of the like. Cut small: However, if the pieces are cut small enough that the addition of the liquid will combine and unite with the solids to form one food then this is forbidden [unless made into a thin batter using an irregularity]. [See footnote for explanation and for a list of vegetables which may be allowed even if cut small[37]] Cooked fruits/vegetables:[38] There are opinions which say that cooked foods which are now soft and easily mash-able do not contain the kneading prohibition and thus one may add liquid to them and knead the liquid into it even into a thick batter, using the regular methods. According to them one may thus add any liquid to mashed potatoes, or to cut pieces of cooked potatoes even if doing so makes it into a thick batter.   Q&A on mixing two semi solids together Is mixing two solids or semi-liquids together defined as Lash if they unite and become one?[39] Dough with dough/bread with bread: Some Poskim[40] rule the kneading prohibition does not apply in such a case Other Poskim[41] however question that perhaps the kneading prohibition applies even in such a case. Semi-liquids such as cheese with honey: Some Poskim[42] rule the kneading prohibition does not apply in such a case Other Poskim[43] however question that perhaps the kneading prohibition applies even in such a case.   May one mix sugar with cocoa powder?[44] So long as no water is added this is allowed as the substances do not stick to each other and is thus not considered kneading.   May one combine honey with cream cheese? Some rule[45] this may not be done as it will be made into a thick mixture. Others[46] however question this prohibition.[47]   May one make thousand island dressing on Shabbos? May one mix mayonnaise with ketchup? This is dependent on the same dispute mentioned above. According to the lenient opinion above, this is allowed to be done[48] so long as one mixes the ingredients slowly. However, according to the ruling of the stringent opinion above, seemingly in their opinion here too it would be forbidden.   May one combine two different yogurts, or yogurt with soft cheese?[49] Some rule[50] this may be done so long as one makes it into a thin batter using the mentioned irregularities. Others[51] however rule this may be done without restriction.[52]   May one mix Chumus with Tehina? This is dependent on the same dispute mentioned above. However, the Chumus and Tehina have water in them, and are considered pre-kneaded, and hence seemingly have greater room for leniency.   May one mix the fruit on bottom of a yogurt? Yes, however according to the stringent opinion it should be done with an irregularity.   May one break biscuits into his yogurt? This may be done so long as either a) the biscuits are broken to slightly large pieces [as opposed to crumbs] or b) the biscuits are broken small but the mixture will form a thin batter and is done with an irregularity.   May one add sugar to soft cheese or yogurt?[53] One may not add sugar to soft cheese as doing say may thicken the mixture and turn it into a thick batter. However, one may add it into yogurt, being that it makes it thinner.   May one combine cocoa powder with butter or margarine?[54] No as doing so forms a thick mixture.

If one transgressed and kneaded a food on Shabbos may the food be eaten?[55] Bimeizid: Forbidden until after Shabbos. Beshogeg: If one transgressed a Biblical kneading prohibition according to all opinions, such as one made a thick batter of kneadable material, then the food is forbidden in benefit until after Shabbos for all people. If, however, only a Rabbinical prohibition was transgressed, such as one made a thin batter without the irregularities required by the Sages, then it is permitted to be eaten by all on Shabbos. If one made a thick batter of un-kneadable material, in which there is a dispute as to whether one transgressed Biblically or Rabbinically, one may be lenient to eat the food on Shabbos.[56]

May one pour liquid or urinate onto earth?[57] Loose earth:[58] Even if doing so does not contain a planting prohibition[59] doing so is forbidden due to the kneading prohibition.[60] [However, if there is no other area to urinate then one may be lenient to do so.[61]] Hard earth:[62] It is permitted to pour water or urinate over hard earth if doing so does not contain a planting prohibition.   May one pour liquid or urinate onto Sand/Ash:[63] It is forbidden to urinate or pour liquids over sand, ash and all items of the like. [Thus, children that have reached the age of Chinuch are to be prevented from playing with sand and water on Shabbos.[64]] In a time of need: If there is no other area to urinate then one may be lenient to do so.[65]   May one pour liquid or urinate onto mud?[66] Very liquidy mud: If the mud is very liquidly, like a mud puddle than this is allowed. Thick mud: If the mud is still slightly thick, it is forbidden to be done due to the kneading prohibition.[67] Hard and dry mud: Even if the mud is hard and dry it is forbidden to urinate on it, as the mud will soften due to the urine.[68] Time of need: Some Poskim[69] rule that in a time of need one may urinate on the mud if the mud does not belong to him.[70]   May one spit into a vessel or area which contains sand/dirt?[71] It is proper to avoid doing so[72] although there is much room to side that this is allowed to be done[73], and so rule some Poskim[74].   May one cover liquid [such as urine] with sand/dirt?[75] One may only do so with a large ratio of dirt/sand over water to the point that the mixture will not form a knead-able substance.

Beating an egg:[76] It is forbidden to beat an egg[77] quickly in a bowl on Shabbos.[78] Rather, one is to mix it slowly with a spoon.[79]   May one mix two liquids into each other?[80] Yes, doing so does not resemble kneading at all.[81] Nevertheless, it is forbidden to mix very quickly with a spoon, or other utensil, thick liquids into thin liquids[82], such as to mix an egg into wine.[83] It is however permitted to mix two thin liquids very quickly, such as lemon juice and water and cases of the like. Seemingly when mixing concentrated juice or oil into water one is to be stringent to do so slowly.[84] Mixing sugar and water quickly:[85] When mixing two items of which one is not recognizable within the other, such as mixing sugar into water, it is permitted to mix them together quickly with a spoon. Mixing salad dressing: One may not mix salad dressing very quickly using a spoon if it contains a thick liquid, such as oil with lemon juice. He is rather to mix it slowly.   May one mix a batch of lemon aid or other juice very quickly with a spoon? Yes. See above Halacha 1 Q&A.   May one make mayonnaise on Shabbos?[86] No.[87]   May one ice cream on Shabbos?[88] No.[89] This applies even if one makes it into a very thin batter.[90]   May one whip cream on Shabbos?[91] No.[92]   May one use a whip cream or confetti spray can on Shabbos? No, due to Molid.

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[1] Piskeiy Teshuvos 321:8; See Shabbos Kehalacha 22:78

^[2] Igros Moshe 4:74 Lash 12; Shabbos Kehalacha 22:78; Shmiras Shabbos Kihilchasa chapter 8 Halacha 25, in the name of the Chazon Ish [Orach Chayim 56:9]. Vetzaruch Iyun Gadol as why here even a thin batter is prohibited. Even the Mishneh Berurah himself [chapter 337:52], to whom they mention in the footnote only says that to make it thick is forbidden, as well as in all cases the food somewhat sticks together, and under what basis can one prohibit it?

[3] Shabbos Kehalacha p. 73

[4] Beir Moshe 6:45; Sheivet Halevy 7:41

[5] As doing so forms a thick mixture which is forbidden to be done on Shabbos. Furthermore, some prohibit doing so due to Nolad.

[6] See Igros Moshe 4:74 Lash 12 which allows making pudding into a thin batter.

[7] SSH”K [new edition]; Shabbos Kehalacha 22:60; Piskeiy Teshuvos 321:27-7 and footnote 270; And so is the ruling according to Tehila Ledavid 321:21 and Ketzos Hashulchan 130:3 footnote 8 in name of Igleiy Tal 30 that so is ruling according to Rebbe Yehuda, brought in Michaber 321:16; Implication of Biur Halacha 321 “Yachol Learbevo” which negates the explanation of P”M 321 M”Z 13 and implies that by Bar Gibul, even according to Rebbe Yossi there would be a prohibition in doing so; So rules also Chazon Ish 58:8-9; however see SSH”K 8:7 who allows adding other liquids to the food even if it was not mixed with external liquid before Shabbos; See Piskeiy Teshuvos 321:25 

[8]The reason: This matter follows the same dispute as mentioned above [in Halacha 1]. According to the first opinion mentioned the mixture is already considered kneaded, and thus adding liquid is allowed. As according to the first opinion the prohibition of kneading is simply to join two items into one, which is accomplished even when kneading food with its own liquid. However according to the second opinion the mixture is not considered previously kneaded unless it was kneaded with a substance other than its own. As they hold that the main aspect of kneading is the adding of ingredients, and here no ingredients were added, as the food naturally came with it. Therefore, according to them in the above cases remain forbidden to add water on Shabbos to the mixture. The final ruling: As was explained above we are stringent like both opinions, and thus this may not be done [unless made into a thin batter with an irregularity]. To note that when the food is Bar Gibul [as is the case with Tehina], then according to some Poskim this would be forbidden even according to Rebbe Yossi, as explained above from M”B.

[9] See above Q&A regarding the definition of a thin batter.

[10] Or Letziyon 2:33-7; Many Rabbanim including Yalkut Yosef; Rav Avraham Yosef; Rav Dov Lior; Tehila Ledavid 321:21 that so is ruling of first opinion in Michaber 321:15 as explained in P”M 321 M”Z 13 [brought in M”B 321:? and Biur Halacha ibid] that if the mustard was kneaded with its juice before Shabbos it may be kneaded even into a thick mixture on Shabbos with a Shinuiy.

The reason: As the Melacha of Lash is only when one connects pieces together and not when one dilutes a food.

[11] Shabbos Kehalacha 22:70

[12] As it is forbidden to make a thick batter on Shabbos.

[13] Nishmas Shabbos 321:305; Orchos Shabbos 6:18 footnote 46; Shabbos Kehalacha 7:61

[14] Although a thick mixture is made since this is un-kneadable material [which according to the first opinion may always be made with an irregularity] and it is unclear if this form of mixture contains at all a kneading prohibition [as the food is cooked, and had water placed in it before Shabbos through the cooking], we are thus lenient [like the first opinion] to allow making it on Shabbos.

[15] Shabbos Kehalacha 22:70

[16] Nishmas Shabbos 321:305; Orchos Shabbos 6:18 footnote 46; ; So I saw ruled in the name of Rav Shternbuch

The leniencies of tuna is that it is unclear if it is at all a material which contains a kneading prohibition. Furthermore, all tuna comes with either water or oil, and is hence considered kneaded before Shabbos to which one may add more liquids on Shabbos. [See above Halacha 4 Q&A]

[17] Shabbos Kehalacha 22:3

[18] Nishmas Shabbos 321:305; Orchos Shabbos 6:18 footnote 46; ; So I saw ruled in the name of Rav Shternbuch

The leniencies of tuna is that it is unclear if it is at all a material which contains a kneading prohibition. Furthermore, all tuna comes with either water or oil, and is hence considered kneaded before Shabbos to which one may add more liquids on Shabbos. [See above Halacha 4 Q&A]

[19] Shabbos Kehalacha 22:70

[20]The reason: As it is forbidden to make a thick batter on Shabbos due to the kneading prohibition.

[21] Nishmas Shabbos 321:305; Orchos Shabbos 6:18 footnote 46; Shabbos Kehalacha 7:61; So I saw ruled in the name of Rav Shternbuch

[22]The reason: As from their understanding, there is no prohibition of mixing mayonaise with a solid on Shabbos even in accordance to Rebbe Yehuda, and therefore, since the mixture is Eino Bar Gibul, it does not transgress the laws of kneading at all. [See Shabbos Kehalacha ibid]

[23]The reason: Although a thick mixture is made, since this is un-kneadable material [which according to the first opinion may always be made with an irregularity] and the food is cooked, and had water placed in it before Shabbos through the cooking, therefore even according to the opinion of Rebbe Yehuda, there is no kneading prohibition involved. This certainly applies with tuna that was in a can in which it actually sat in liquid, and hence whether according to Rebbe Yehuda, or Rebbe Yossi, it is permitted to be kneaded, as according to Rebbe Yehuda it was already pre-kneeded, and according to Rebbe Yossi it is Eino Bar Gibul which may always be kneaded with an irregularity. [See Admur 324:3]

[24] Shabbos Kehalacha 22:70

[25] Nishmas Shabbos 321:305; Orchos Shabbos 6:18 footnote 46

[26]The reason: As we are initially stringent like the opinion who holds it is forbidden to knead even Eino Bar Gibbul, and here there is no added Heter of it being pre-kneaded, as it is not cooked in other liquids.

[27] SSH”K 8:3

[28] Ketzos Hashulchan 130 footnote 19 and SSH”K 8:14; Shabbos Kehalacha 22:41

[29] 58:9

[30] SSH”K 8:18

[31] As it does not resemble in any way the concept of kneading, as explained in Halacha 2 in Q&A there with regards to the definition of a thin batter. It is only when there is some thickness to a mixture that it is within the kneading requirements of an irregularity

[32] As rules Rav Farkash with regards to instant coffee. See The laws of cooking Halacha 12 Q&A there!

[33] Vetzaruch Iyun how this case is any different than any case in which the added liquid at first thickens the food and only after further mixing does it thin it out, of which was explained in Halacha 3 Q&A that it is forbidden to do so. Perhaps however the difference is that here one has no intent to knead the powder but to dissolve it and thus it is considered a Pisek Reishe, of which we are lenient in being that anyways according to one opinion this is always allowed with an irregularity. However, by cases where one intends to knead the food, then although his intent is to make it into a thin batter nevertheless since it becoming a thick batter also serves his use, it is not allowed. See SSH”K 8 footnote 61.

[34] Igros Moshe 4:74 Lash 1

[35] See SSH”K 18 and 24 and footnote 56. Vetzaruch Iyun why they did not mention explicitly that if it does not dissolve right away an irregularity is to be used, as they wrote by milk powder.

[36] Taz 321:12 in name of Bach regarding lettuce; Ketzos Hashulchan 130:6 footnote 19; Shevisas Hashabbos Pesicha 20; SSH”K 8:4; Piskeiy Teshuvos 321:27

[37] This ruling is based on Taz 321:12 which rules that the allowance to cut vegetables small and then add liquid to them is only in accordance to the first opinion being that vegetables are not a knead-able food however according to the second opinion this would be forbidden, [unless made into a thin batter with an irregularity]. Thus, since we rule like the stringent opinion it would be forbidden for us to make a thick mixture of radish. Nevertheless, many are accustomed to be lenient by radishes even if they are cut small. The Taz there writes the reason for this being due to that if one were to make the mixture before Shabbos its taste would be ruined, and it was therefore allowed to do so on Shabbos with an irregularity, relying on the first opinion above. The Ketzos Hashulchan [ibid] as well suggests that perhaps the reason for this leniency by radishes is because the concept of kneading only applies by foods which will stick together to the liquid, such as garlic and the like. However solid vegetables, even when very small, which will not form a real combination with a liquid would be allowed to be mixed even into a thick batter. In any event this is certainly not the opinion of the Taz which mentions explicitly the case of radishes as a case of kneading. The Ketzos Hashulchan [ibid], based on the Taz and Shevisas Hashabbos, rules that by radishes one may be lenient however not by horseradish/beats or any vegetable which secrets a juice which will cause the mixture to stick.

[38] SSH”K 8:19-See above Halacha 5 Q&A

[39] Shabbos Kehalacha 22:49; Piskeiy Teshuvos 321:24-25

[40] Shevisas Hashabbos Lash 8-9 as one is not uniting two different species of foods; Orchos Shabbos 6:20; Nishmas Shabbos 321:306; Igros Moshe 4:74-13; Chut Hashani 13:2 as the kneading prohibition only applies when mixing a liquid with many solids to join and become one soild.

[41] Rav SZ”A 8 footnote 13 as perhaps the prohibition applies anytime one unites two pieces together through moisture.

[42] Orchos Shabbos 6:20; Nishmas Shabbos 321:306; Igros Moshe 4:74-13; Chut Hashani 13:2 as the kneading prohibition only applies when mixing a liquid with many soilds to join and become one soild.

[43] Shevisas Hashabbos Lash 11; Rav SZ”A 8 footnote 13 as perhaps the prohibition applies anytime one unites two pieces together through moisture.

[44] SSH”K 8:5

[45] SSH”K 8:13

[46] Rav Avraham Elyashvili

[47] As in their opinion these kneading only applies by a solid with a liquid and not by two semi-liquids. Perhaps however there is difference between whether the cream cheese and honey is thick or thin.

[48] As ketchup with mayonnaise are both semi liquids and thus are not subject to kneading which is with a liquid and a solid.

[49] SSH”K 8:12

[50] SSH”K 8:12

[51] Igros Moshe 4:74 Lash; Rav Avraham Elyashvili mentioned in Rav Gadasi’s Hilchos Shabbos

[52] As in their opinion these kneading only applies by a solid with a liquid and not by two semi-liquids.

[53] SSH”K 8:16

[54] SSH”K 8:17

[55] Biur Halacha 321:16 “Aval Beshabbos”; Shabbos Kehalacha 22:28

[56] Biur Halacha ibid in name of Elya Raba

[57] Ketzos Hashulchan 130:8

[58] M”A 321:19 regarding mud; P”M 321 A”A 19; M”B 321:57; Ketzos Hashulchan ibid

[59] See Admur 336:9; The Laws of Shabbos Volume 3 “Plants trees and Garden produce” that urinating on earth is from the letter of the law not prohibited due to the sowing, and that earth which is not designated for sowing and is not near plants or trees does not contain the sowing prohibition even with water.

[60]The reason: This is Biblically forbidden according to Rebbe Yehuda, and is Rabbinically forbidden according to Rebbe Yossi. [ibid]

[61] Beis Meir brought in M”B 321:57; Implication of M”A ibid which motions the reader to Michaber 320:14 which brings a dispute if one may urinate on snow, and regarding that dispute Admur rules that in a time of need one may do so, and here too seemingly it is allowed as the main ruling is like Rebbe Yossi that there is no prohibition until one actually kneads the liquid. [See P”M 321 A”A 19]

[62] Ketzos Hashulchan ibid; Aruch Hashulchan 321:25; Chazon Ish 58:8

[63] P”M ibid; M”B ibid; Ketzos Hashulchan ibid

[64] SSH”K 16:4

[65] Beis Meir brought in M”B 321:57; Implication of M”A ibid which motions the reader to Michaber 320:14 which brings a dispute if one may urinate on snow, and regarding that dispute Admur rules that in a time of need one may do so, and here too seemingly it is allowed as the main ruling is like the Rambam in the opinion of Rebbe Yossi that there is no prohibition until one actually kneads the liquid, and that there is no prohibition by Eino Bar Gibul. [See P”M 321 A”A 19]

[66] Ketzos Hashulchan 130:8

The reason there is no allowance due to the rule of “Ewin Lash Acchar Lash”: As the mud still requires more water for its kneading or the mud is hard and dried, hence entering into the Lash prohibition. [Ketzos Hashulchan ibid footnote 3; Shevisas Hashabbos Lash 6]

[67]The reason: This is Biblically forbidden according to Rebbe Yehuda, and is Rabbinically forbidden according to Rebbe Yossi. [ibid]

[68] Peri Megadim 321 A”A 19 leaves this matter in question being that the mud eventually melts due to the liquid; brought in M”B 321:57 and Shaareiy Tziyon 321:66

[69] M”B 321:57; Beis Meir brought in M”B ibid permits in all cases in a time of need

[70]The reason: As this is considered a Piseik Reisha Delo Nicha Lei on which one may be lenient in a time of need. [ibid] To note however that Admur rules stringently regarding Pesik Resihei Delo Nicha Lei even by a Rabbinical prohibition, as brought in 316:4 and 320:24]

[71] Ketzos Hashulchan 130:8 footnote 22

[72] The Peri Megadim ibid [brought in M”B ibid] leaves this matter in question due to the following reason: According to the second opinion mentioned above, even entering liquid into a non-kneadable material constitutes a Biblical kneading prohibition, and thus perhaps there is no room to permit the spitting. On the other hand perhaps in this case one can be leniently as he has no intent to knead the material with his saliva, and it’s a case of “Pisek Reshei Dilo Nicha Lei”. [P”M ibid]

[73] So rules Ketzos Hashulchan based on that a) spitting is an irregularity and thus only Rabbinical. B) The amount that can be mixed is less than the Biblical amount needed to transgress kneading. C) Naturally saliva does not sink into material but rather floats over it.

[74] Beis Meir, brought in M”B ibid

[75] Chayeh Adam; M”B 321:57; Ketzos Hashulchan 130:8

[76] M”A  321:24; M”B 321:68; Shabbos 109a

[77]Other opinions: Some Poskim rule it is permitted to beat a single egg and the prohibition only applies to more than one egg at a time. [Tiferes Yisrael Ofeh 11]

[78]The reason: Being that this appears like one plans to cook it on Shabbos. [M”A ibid; Rashi ibid] Doing so is forbidden due to Uvdin Dechol. Others rule the reason is because doing so is considered kneading. [Peri Megadim 321 A”A 24] According to the first reason the prohibition is limited only to eggs. According to the second reason the prohibition extends to all matters, as states M”A ibid in name of Hagahos Maimanis 22 and P”M ibid. [Machatzis Hashekel ibid]

[79] Ketzos Hashulchan 130:7; Chayeh Adam 20:21

[80] Based on Magen Avraham 321:24 as explained in Ketzos Hashulchan 130:7 footnote 20

[81] In Yoreh Deah 266:3 the Michaber rules that wine must be mixed with oil from before Shabbos, and so rules Admur in 331:1. The reason for it being forbidden is not because of a kneading prohibition but because doing so was considered a medicine, and it is forbidden to make a medicine on Shabbos. [So writes Admur there]

[82] So seems evident from all sources listed regarding this law that the prohibition is only applicable when mixing a thick liquid into thin. [See Ketzos Hashulchan ibid; Chayeh Adam 20:21; Peri Megadim A”A 321:24 “As it appears like kneading when making thick”] However to mix two liquids into each other very quickly there is no restriction. This is also implied in the meaning of “Litrof” to beat rather than simply mix. Now, although the Magen Avraham 321:24 brings from the Hagahos Maimanis that one may not mix Zirga wine very quickly. It is unclear as what this wine consists of, and perhaps in truth it does consist of two items of which one is thick and the other thin. [See Beir Yaakov 321 which explains this to be the case]. Furthermore, although the M”A concludes “and so it seems from the Hagahos Maimanis that it is forbidden to beat all matters” perhaps this is only coming to include other thick liquids similar to eggs, and is not coming to include all liquids. [See Machatzis Hashekel that this is coming to exclude the opinion of Rashi which rules the prohibition against beating is only by eggs as it appears one is doing so for cooking purposes.] As for the reason it is forbidden to beat two liquids very quickly perhaps this is because it is considered a troublesome act [as writes M”A 321:25 regarding making “Yaynomalin”]. Accordingly, it would be permitted to mix two thin liquids, as doing so involves no trouble at all.

[83] Magen Avraham 321:24-25

The reason: As for the reason it is forbidden to beat two liquids very quickly perhaps this is because it is considered a troublesome act [as writes M”A 321:25 regarding making “Yaynomalin”]. Alternatively, the reason is because doing so is considered kneading. [Peri Megadim 321 A”A 24] Accordingly, it would be permitted to mix two thin liquids, as doing so involves no trouble at all and is not similar to kneading.

[84] As the definition of a thick liquid brought above is unclear. Vetzaruch Iyun.

[85] Ketzos Hashulchan ibid.

[86] Tzitz Eliezer 12:32; SSH”K 11 footnote 128

[87]The reason: As it is forbidden to beat an egg on Shabbos. [Magen Avraham 321:24]

[88] Betzeil Hachachmah 2:26; Piskeiy Teshuvos 321:30

Other opinions: Some write it is permitted to make ice cream on Shabbos. [SSH”K 10:6]

[89] This is forbidden due to it being similar to making “Yaynmulin” which is a mixture of wine pepper and oil, of which it is forbidden to beet and then strain due to it being a great trouble. [See Magen Avraham 321:25; Michaber 321:17; Mishneh Shabbos 139b]  Alternatively, the reason is because doing so is considered kneading. [Peri Megadim 321 A”A 24; Chemed Moshe 321:6; Biur Hlaacha 321:15 “Yachol”] It is likewise forbidden due to Nolad-forming a new matter on Shabbos. [SSH”K ibid]

[90] As the prohibition is not due to kneading. In truth however making ice cream into a thick batter would certainly transgress also the kneading prohibition.

[91] SSH”K 11:31 in name of Rav SZ”A; Piskeiy Teshuvos 321:30

[92] This is forbidden due to it being similar to making “Yaynmulin” which is a mixture of wine pepper and oil, of which it is forbidden to beet and then strain due to it being a great trouble. [See Magen Avraham 321:25; Michaber 321:17; Mishneh Shabbos 139b]  Alternatively, the reason is because doing so is considered kneading. [Peri Megadim 321 A”A 24; Chemed Moshe 321:6; Biur Hlaacha 321:15 “Yachol”] It is likewise forbidden due to Nolad-forming a new matter on Shabbos. [SSH”K ibid]