May one sprinkle icing sugar on doughnuts with a sieve on Shabbos? [1]

Local custom “dictates” the consummation of doughnuts (sufganiot) on Chanukah and the doughnuts are sprinkled with icing sugar, preferably through a sieve to spread it evenly. It would seem to be totally accepted to use a sieve in this instance because it is not used to separate between ‘bad’ and ‘good’, rather used to spread evenly.

So l’ma’ase, may one use it?

The Shulchan Aruch writes [2] that if one wishes to sift flour on Yom Tov for the second time (improves the bread) one may do so albeit with a shinui. The Mishna Berura [3] explains that without a shinui people might confuse this sifting with the first initial sifting, which may not be done on Yom Tov. We can infer that using a sifter for whatever reason is not permitted, because people might confuse a permitted use with a non-permitted one. It is therefore recommended that one ask a rav.

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

Borer or separating is complicated on Shabbos and on Yom Tov and a slight deviation from the rules involves a d’oraisso. For example, we know that on Shabbos one may remove ochel from p’soles, (good from bad) - for immediate consumption. The Mishna Berura writes [4] that if one removes p’soles from ochel one has violated a d’oraisso. [5]

Does this apply to Yom Tov as well?

Borer is permitted in many cases on Yom Tov on account of ochel nefesh [6] although in certain cases it is not permitted. One must know the halacha for each case before being lenient.

How is this done?

The rule is that one must separate a mixture in the easiest manner possible. One must therefore separate a piece of carp from the bones in the easiest manner. If easier to remove the bones from the fish, one must do so; if easier to remove the fish from the bones, one must do so.

What does “easier” have to do with anything?

As stated, on Yom Tov one may separate good from bad or bad from good, which ever is easier. The Shulchan Aruch HaRav explains that although borer is permitted, extra tircha (unnecessary labor) was never permitted. One may therefore separate on Yom Tov for a Yom Tov meal and must be done with the least tircha possible. [7]

• More good than bad – remove the bad, e.g. remove bones from carp and watermelon seeds from watermelon.
• More bad than good - remove the good from the bad.
• The good is fine particles but less in quantity – in which case it is easier to remove bad from good even though there is more bad than good. One must remove the bad to minimize tircha.

What if I could have separated good from bad before Yom Tov?

In that case the Bi’ur Halacha writes [8] that it is correct to separate in the same manner one would on Shabbos. This is because even though borer is done for ochel nefesh, nevertheless the rule is that something that could have been done before Yom Tov requires a shinui when done on Yom Tov.

He writes that not all rule like this and therefore one who is not stringent has what to rely upon. [9]

So should I remove the carp from the bones even though it’s more tedious?

Carp bones cannot be separated before Yom Tov as one separates when eating it, consequently one should separate in the easiest manner possible.

May one peel potatoes with a peeler?

Many are accustomed to peel with a peeler on Shabbos, as it is viewed as a sophisticated knife and not an item specifically used for borer. [10] Even those who are stringent and do not peel with a peeler on Shabbos may do so on Yom Tov. [11]

Rav Shlomo Zalman Auerbach explains that only a k’li used for preparation many days in advance may not be used on Yom Tov and a peeler does not fall into that category.