We have already discussed that there is a Mitzvah to recite the Hamotzi blessing during the Shabbat meals on “double bread,” i.e. two loaves of bread. It is fairly common that one does not have two loaves of bread for this Mitzvah and would like to join a frozen loaf of bread from the freezer (which is presently inedible) to the fresh loaf in one’s hands. The question is, is it proper to do so or can such a loaf of bread not be used for the Mitzvah of “double bread”?
We have also discussed that there is no obligation to break both loaves of bread during the Shabbat meal, for the Mitzvah of two loaves of bread applies only when the Hamotzi blessing is recited and one only needs to break one loaf. The Rashba writes likewise in the name of Rabbeinu Hai Gaon, as do several other Rishonim. If so, since there is no obligation to break both loaves of bread, it seems that it is permissible to recite the blessing on both even though one is currently inedible.
Although the loaf of bread is inedible as long as it is frozen, nevertheless, Maran Rabbeinu Ovadia Yosef zt”l writes that since it will indeed be edible when it thaws and no further action is necessary in order to make it edible, it is thus presently considered worthy for use for the Mitzvah of “double bread.” The proof to this is based on what Hagaon Rabbeinu Akiva Eiger writes regarding a loaf of bread which became forbidden for consumption because it was baked on a Yom Tov preceding Shabbat (it is forbidden to prepare on Yom Tov for Shabbat and if one does so, the food is forbidden for consumption), it is nevertheless permitted to use this bread for the Mitzvah of “double bread” since the bread is only prohibited for consumption by means of a rabbinic decree and will be permissible for consumption at a later time; it is therefore permissible to act leniently and use this loaf to fulfill the Mitzvah of “double bread.” Based on this, the same would apply to a frozen loaf of bread, for although it is presently inedible, nevertheless, since it will be edible later, it may be joined with the other loaf of bread for the Mitzvah of “double bread” when no other bread is available.
Thus, halachically speaking, a frozen loaf of bread may be used to fulfill the Mitzvah of “double bread.” One who is stringent and borrows another loaf of bread which is already edible from a neighbor shall surely be blessed.