3,239. How Much Terumah is Enough?
Terumos 3:1
There is no minimum measure for terumah gedolah under Torah law. Deuteronomy 18:4 says, “The first of your grain,” meaning even the smallest volume. Even a single kernel would fulfill the obligation for the entire pile of grain. Optimally, one separates terumah based on the measures set by the Sages. Nowadays, since terumah is burned because of ritual impurity, one may separate even the smallest amount at the outset.
Terumos 3:2
The measures that the Sages set are as follows: 1/40 of the harvest is generous; 1/50 is average; 1/60 is ungenerous. One doesn’t give less than 1/60.