Tevul Yom 1:1-2

T’vul Yom 1:1

If a person collected pieces of challah (portion of the dough) intending to keep them separate but they got stuck together, Beis Shammai say they are considered connected vis-a-vis a t’vul yom (one who has immersed but is awaiting nightfall to be ritually clean; since the pieces of dough are considered connected, if he touches one, he transmits impurity to them all); Beis Hillel say they are not considered connected. Regarding pieces of (trumah) dough that got stuck together, loaves that stick together, if a person bakes one cake of batter on top of another before it can form a crust in the oven, or if the froth on water was bubbling, or regarding the first scum that rises from boiling beans or the scum of new wine – and Rabbi Yehuda adds that of rice – Beis Shammai say that all of these are considered connected for a t’vul yom; Beis Hillel say they’re not considered connected. Both schools agree that they’re considered connected for any other kind of impurity, whether minor or major.

T’vul Yom 1:2

If one collected pieces of challah without intending to separate them later, or if one cake of batter was baked on top another after the crust formed in the oven, or if froth appeared on water before it bubbled, or regarding the second scum that rises from boiling beans, or the scum of old wine, of any kind of oil or of lentils – and Rabbi Yehuda adds that of beans – all of these are rendered unclean when touched by a t’vul yom, and it goes without saying that this is so with other sources of impurity.