3,348. Terumah Repeatedly Falling Into Secular Produce
Terumos 13:4
The previous halacha (about mixtures of produce) applies to things that don’t blend together, like kernels of wheat or flour. When it comes to things that do blend together, like terumah oil with secular oil or terumah wine with secular wine, we follow the majority. If the greater volume of the mixture is terumah, then if it falls into other produce, it’s treated as if it was all terumah. If the greater volume of the mixture is secular produce, then if the mixture falls into other produce, the original mixture is treated like secular produce and it doesn’t create meduma. This is so even though that first mixture is prohibited to non-kohanim.
Terumos 13:5
Let’s say that a seah of terumah falls into 100 seah of secular produce, a seah of the resulting mixture is removed, another seah of terumah falls in, another seah of the resulting mixture is removed, and another seah of terumah falls in. In such a case, the secular produce remains permitted until the terumah constitutes the greater part of the volume. Therefore, if more than 100 seah of terumah falls into 100 seah of secular produce in this piecemeal fashion, then the mixture is rendered meduma.