Ask the Rov: Can I make pickled cucumbers on Shabbos?
By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah
Chazal tell us that “pickling (kavush) is like cooking,” and just as one may not cook on Shabbos, one may not either pickle a vegetable on Shabbos. Alternatively, pickling resembles the melacha of tanning (which also uses salt). While some hold it is a prohibition min haTorah, the accepted halacha is that it is miderabanan.1
Halacha considers “pickling” to occur when a vegetable is either soaked in any liquid for 24 hours, or in vinegar or strong acidy liquids for merely 18 minutes.2 Some acharonim hold that these times apply specifically to the transfer of taste in the halachos of kashrus, while the Shabbos prohibition applies only to the amount of time it takes for the vegetable to become pickled.3
Is pickling for a shorter amount of time permissible?
On Shabbos, there is concern of activity that “appears like pickling,” which applies to the act of putting vegetables in vinegar for any amount of time.4 Yet, when the intention is just to flavor, or when flavoring food to be eaten in that same meal, one is allowed to put a small amount of vinegar.5
Once the vegetable is adequately pickled, there is no prohibition to pickle it further by returning it into the jar, as there is no “pickling after pickling” (just as there is no “bishul achar bishul,” cooking after cooking). Yet, a partially pickled vegetable may not be returned into the pickling jar for it to continue pickling.6
If it was already pickled in vinegar, and one wants to pickle it now in salt water, some poskim permit it since it is already pickled, while others argue that since it introduces a new flavor, it is prohibited at least on account of “appearing like pickling.”7
The concern of “appearing like pickling” only applies to foods that are normally pickled (i.e. their natural state is changed through pickling), but does not apply to foods like cooked eggs and meat. These foods may be soaked in brine for a short amount of time.8
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From The Weekly Farbrengen by Merkaz Anash