2,391. Kashering a Wine Vat
Maachalos Assuros 11:20
If a non-Jew trod grapes in a stone or wood vat, or if a non-Jew applied pitch to a stone vat even without treading the grapes, the vat must be thoroughly rinsed four times with water and ashes. After this, grapes may be tread in the vat. If the vat is still damp, the ashes should be put in before the water; otherwise, the water should be put in first.
Maachalos Assuros 11:21
If a non-Jew trod grapes in a stone vat covered with pitch, or if he applied pitch to a wooden vat even without treading grapes in it, the pitch must be peeled off. If it was left for 12 months or filled with water for three days, then it need not be peeled. A wine vat need not be treated more stringently than barrels. Peeling was only allowed in order to permit the vat for immediate use.