3,623. Today There's No Ritually Clean Dough

Hilchos Bikkurim 5:9

Nowadays, since there is no ritually clean dough because of corpse impurity, one challah of 1/48 of a dough is taken in throughout Israel. Even though it is burned because of its impurity, the requirement to separate challah is a Biblical obligation. As was the case previously, a second challah is taken from K’ziv to Amanah for a kohein to eat. There is no minimum volume required for this second challah.

Hilchos Bikkurim 5:10

Even though challah from outside of Israel is ritually unclean, since it’s required by Rabbinic law, it is only prohibited to kohanim who are unclean because of a bodily form of impurity, like one who had a seminal emission, a zav, a zavah, a niddah, a woman who gave birth and a metzora. Those who are unclean from external sources of impurity – even from a corpse – may eat it. Pursuant to this, let us discuss a kohein who is a minor and outside of Israel – whether in Syria (i.e., lands annexed by Israel) or elsewhere. If a person wants to take just one challah, he can separate 1/48 of the dough. This may be eaten by a kohein who is a minor who never experienced a seminal emission, or a bas kohein who has not yet gotten her period. A person in such a case need not take a second challah.