Melacha #10: LOSH - DOUGH-MAKING (lit. KNEADING)

Av Melacha: Mixing flour and water (and kneading a dough).

Principle: Different approaches in the Talmud and commentators (Rishonim) explain the principle of the Melacha:

The first opinion sees Losh as forming a dough-like substance from a solid and liquid. This approach is the Sephardic custom.

Other opinions view Losh as combining any two substances that have different consistencies to form one thick (though not necessarily dough-like) consistency. This approach is the Ashkenazi custom.

Toldot:

According to the first opinion: actual dough-making, cement mixing, preparing a plaster cast.

According to the other opinions: in addition to the above-mentioned Toldot, mixing sand and water, preparing egg salad, potato salad (small pieces), mixing ketchup and mayonnaise, adding sugar or jam to yogurt.

It is therefore prohibited to make a finely-cut tuna salad on Shabbat by mixing mayonnaise with tuna, because this creates one consistent mixture.

Should it be necessary to create a thick mixture (e.g. for an infant), one could rely on the double-Shinui mentioned below.

Gezeira: Creating a thin and runny mixture (according to all opinions).

The Rabbis permitted making thin and runny mixtures if prepared with two Shinui'im (changes):

1. Shinui in the pouring -- i.e. reverse the order of how the substances are normally combined. If there is no set order, in time of need the solid may be put in first, and

2. Shinui in the mixing -- e.g. mix them in a cress-cross pattern, rather than a circular motion. Or mix with a finger instead of a utensil.

Note: when adding the liquid substance to the solid substance, be sure the solid is immediately absorbed by the liquid, to avoid making a thick (consistent) mixture in the process. One should, therefore, pour quickly.

Further descriptions:

1. It is permitted to coat one substance with another, if they do not join together into one "ball." Examples: adding salad dressing to a salad, or coating tuna chunks with mayonnaise.

2. If something was mixed before Shabbat and became separated, it is permitted to remix it. Example: remixing the oil that rises to the top of peanut butter.

3. If something was mixed before Shabbat, it is permitted to thin it out further on Shabbat by adding more of the same liquid or even water (even if the mixture remains thick).

4. When one substance becomes completely absorbed into the other (i.e. there is no noticeable difference in the liquid consistency of the end product), it is completely permitted. Example: adding instant coffee to a glass of hot water.

5. It is permitted to combine two solids -- e.g. sugar and cinnamon.

Takana: It is prohibited to mix or shake a mixture vigorously, because it resembles Melacha.