Chanoch from Achuzat Brachfeld asks:
I received a lot of sh’mittah wine for Purim. I know
that the time for bi’ur on wine is Erev Pesach. What quantity of
wine is exempt from bi’ur? How do I perform bi’ur on the wine?
If, when Erev Pesach arrives, a person only has in his
possession enough wine to be drunk with three meals for each member of his
household, he is exempt from bi’ur. Since one of the three meals
following the time of bi’ur on wine is the Pesach Seder, at which
one drinks four cups of wine, this is taken into consideration. If one has a
large family (and/or a large number of guests), the quantity exempt is
accordingly increased. Should one have more than this allowance, the extra
quantity must be taken out into the street and declared ownerless in front of
three people. These three can be relatives or friends, who will not take
advantage of this declaration. However, the declaration must be sincere. Once
this declaration has been made, one may retake possession of the wine. There is
then no time restriction for drinking the wine.