Grinding cont.

What about scraping mud from one’s shoes on Shabbos? Does grinding apply somewhere?

            Yes, as explained, grinding mud is a problem of èåçï and although one may gently scrape mud from one’s shoes one must not grind or break up dried mud.

            Is one permitted to mash avocado onto a piece of matza or bread?

            Here one is entering the realm of grinding and we know that one is forbidden to mash or grind in the regular manner. We learned that one may grind salt or pepper on Shabbos by implementing two modifications to the process. It is permitted to crush salt or pepper with a knife’s handle onto a plate or table. The normal way to mash a banana is to use a fork on a plate etc. How is this modified to enable its mashing on Shabbos?

Hagaon Rav Moshe Feinstein ztz”l held [1] that bananas are not subject to the constraints of grinding because the definition of grinding is to crush an article into small pieces, which is not the case when one mashes a banana, rather it remains one piece albeit in a different form.

The Chazon Ish [2] on the other hand held that grinding applies to mashing items such as bananas as well. He held that for a child one may mash a banana with a spoon handle. [3]

Rav Moshe concludes that one l’chatchila should mash a banana with a handle of a spoon (because of the Chazon Ish) and if one finds that difficult one may mash a banana with a fork in the regular manner.

It appears that Rav Shlomo Zalman Auerbach ztz”l [4] was more stringent than R’ Moshe and ruled that one may only mash a banana with either side of a spoon but not with a fork.

Consequently, one should mash avocado with a spoon onto matza or bread.

            Does the heter to mash bananas only apply to children?

            Since one is deviating from the norm and not mashing it in the regular fashion, one may mash it for adults as well, but one should only do so prior to eating. [5]

            Is there a special leniency to mash soft fruit and vegetables?

            Some avocadoes are so soft that when one holds one part of the avocado it simply breaks off. The same happens with vegetables that have been cooking, for example in a soup, for a long time. Rav Shlomo Zalman Auerbach ztz”l held that the issur of grinding does not apply to fruit or vegetables in such a state because it is as if they are already ground. [6] Naturally one must take care that the vegetables have indeed reached the required state.

            Is one permitted to slice hard-boiled eggs with an egg slicer?

            Eggs are not subject to the constraints of grinding as that they are not grown in the earth. Nevertheless one may not grate them with a grater or grinder. An egg-slicer, on the other hand, does not grind eggs, it merely cuts them in a sophisticated manner. [7] Therefore one may slice tomatoes and onions with this instrument as it is not a grinder.

            Are there any limitations as to how one is supposed to make porridge on Shabbos?

            One of the melachos of the Mishkan was ìéùä – kneading, where they would mix flour and water and knead it to form dough. There are many complex details regarding this melacha and we will be”H try and simplify it as much as possible.

The halacha deals with two forms of mixtures, a firm mixture and a liquid one, or a áìéìä òáä and a áìéìä øëä. Making a firm mixture can often involve a biblical violation and therefore the ways to produce such a mixture on Shabbos are very limited. Making a liquid mixture on Shabbos is only an issur d’rabanan (a rabbinic violation) and therefore a wider range of solutions are at hand.

A firm mixture – it is forbidden to mix powder with liquid to form a paste. Accordingly one may not mix humus or mustard powder with liquid to form a paste. It does not help to mix them b’shinui (modify the mixing mode) because it is making a áìéìä òáä. [8]

We define a áìéìä òáä as any mixture that one cannot pour and a áìéìä øëä as a mixture that one is able to pour from one k’li to another. [9]

Taking it for granted that it is forbidden to make a firm mixture on Shabbos we will concentrate on making a liquid mixture.

To answer the question we will say that a thick porridge falls into the category of a firm mixture and as such it cannot be made on Shabbos. See footnote 8.

            How is one to make a liquid mixture on Shabbos?

            Two processes are incorporated in making a mixture and both must be modified in order to permit making a liquid mixture on Shabbos. The first is pouring the liquid into the solid or vice versa and the second is the actual mixing of the two items.

Pouring – if normally one would pour the liquid onto the solid, on Shabbos one must add the solid to the liquid. If normally one would add the solid to the liquid, on Shabbos one must pour the liquid onto the solid. If there is no fixed pattern the Mishna Berura says [10] to pour the liquid onto the solid. [11]

Mixing – normally one mixes the solid and the liquid with a spoon. In order to deviate one may either mix them with one’s finger or shake the k’li. If either method is not feasible one may mix with a spoon but it must be done is a crisscross fashion, i.e. insert the spoon for example in the north of the bowl and run it southwards. Then insert it in the west of the bowl and run it eastwards etc. Continue in this fashion until the ingredients are mixed. The Chazon Ish writes that l’chatchila one removes the spoon from the bowl after each run [12]