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Weekly Halacha Series
Halachos Series on Hilchos Yom Tov

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Published by
Pirchei Shoshanim

A Project of
The Shema Yisrael Torah Network

Written by

Rabbi Dovid
Ostroff, shlita


These Halachos were shown by Rabbi Ostroff to
HaGaon HaRav Moshe Sternbuch, shlita



Questions for the Week of Parshas Noach

May one grind bread and cookies on Yom Tov?

The halacha is that one may grind items that have been previously ground . This is true for Shabbos as well. Consequently one may grind cookies, bread, matzo or almost any ground item because the grains were ground into flour and processed.

Likewise, sugar cubes, caked salt and chocolate may be ground on Yom Tov in the regular manner. [1]

May I measure and weigh food on Yom Tov?

The Shulchan Aruch writes [2] that on Yom Tov one may measure spices intended for the pot in order not to over-spice and spoil the food. This statement implies A) Food that would not spoil may not be weighed. B) One is permitted to measure in the normal manner, because the Mechaber did not limit the method.

Indeed the Mishna Berura writes [3] that one may measure spices accurately to prevent over-spicing, but if one usually estimates amounts and does not measure correct amounts, one may not measure them.

And food that will not spoil?

The Shulchan Aruch writes [4] that one may not measure flour on Yom Tov, rather one should estimate the required quantity. The difference between flour for bread and cake and spices is that if one miscalculated the amount of flour the bread taste, texture and quality will not be affected, whereas miscalculating spices will spoil the food.

What if I need an exact amount of flour?

The Mishna Berura [5] cites the Pri Megadim saying that one may accurately measure flour when accuracy is needed. This is true whenever an exact amount is needed.

Either measuring is permitted or it is not, why the distinction?

Chazal instituted a gzeira against measuring and accurate estimation because it appears that one wishes to sell the produce. When abiding to this rule will cause food to spoil etc. they did not institute the gzeira and hence spices may be measured

It is important to note that a scale may not be used at all; rather one should use a measuring cup or measuring spoon.

Is one permitted to use a sifter on Yom Tov?

A sifter is used to remove non-wanted items from a mixture, such as sifting flour to remove chaff and debris. Sifting, sorting and separating are generally categorized as Borer- separating, which in principle is a permitted melacha on Yom Tov, but has many restrictions.

Sifting flour for the first time is called meraked [6] and is prohibited on Yom Tov, even if one did not have time to sift flour before Yom Tov and it is needed for challos and cake on Yom Tov. [7]

Why is sifting ossur if it is ochel nefesh?

It is a machlokes (dispute) whether it is ossur midoraisso or midrabanan.

The basis to say it is doraisso follows the rule that melachos done prior to lisha (kneading) are biblically prohibited and not included in ochel nefesh. Others hold that it is only drabanan because sifting is usually done for a large quantity of flour many days prior to use. Whatever the case, it is forbidden. [8]

May I remove a fly from my drink on Yom Tov?

Two statements in Shulchan Aruch seem to be a contradiction. The Rama writes [9] that if one wishes to remove a stone or straw from flour one may remove it with ones hand but there are those that are stringent and prohibit it. On the other hand we find [10] that one may separate the foreign bodies in the regular manner when eating legumes (such as beans etc.) without restrictions.

The halacha is that one should not remove a fly from drink or soup with ones hand, as it is normal to do so during the week as well. One should remove some liquid together with the fly or insect, [11] which according to most poskim is permitted on Shabbos as well.

This is contrary to common belief that all borer is permitted on Yom Tov and proves, once again, that Hilchos Yom Tov are not that simple and require much review and learning.

[1] SSK 7:5.

[2] Simon 504:4.

[3] Simon 504:21-22.

[4] Simon 506:1.

[5] Simon 506:2.

[6] Related to dancing, because the items dance in the sieve.

[7] SSK MB simon 506:5.

[8] See MB simon 506:5.

[9] Simon 506:2.

[10] Simon 510:2.

[11] M"B simon 506:12.


Food for Thought

May one sprinkle icing sugar on doughnuts with a sieve on Shabbos?

How is one to remove bones from fish on Yom Tov?

May I squeeze oranges on Yom Tov?

Answers coming BE"H next week.

Vort on the Parsha

And Noach did everything as Hashem told him. The Ksav Sofer explains that Noach kept the seven Noahide mitzvos as commanded to Adam and passed to Noach (Rambam Melachim 9:1). But when commanded directly and specifically by Hashem he should have danced for joy that he had the opportunity to perform a direct commandment. The possuk says that Noach did everything as Hashem told him. In other words he did not inject special simcha and fervor into this mitzvah.

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Note:  The purpose of this series is intended solely for the clarification of the topics discussed and not to render halachic decisions. It is intended to heighten everyone's awareness of important practical questions which do arise on this topic.  One must consult with a proper halachic authority in order to receive p'sak.