תְּרוּמָה גְּדוֹלָה אֵין לָהּ שִׁעוּר מִן הַתּוֹרָה. שֶׁנֶּאֱמַר (דברים יח ד) "רֵאשִׁית דְּגָנְךָ" כָּל שֶׁהוּא אֲפִלּוּ חִטָּה אַחַת פּוֹטֶרֶת הַכְּרִי. וּלְכַתְּחִלָּה לֹא יַפְרִישׁ אֶלָּא כַּשִּׁעוּר שֶׁנָּתְנוּ חֲכָמִים. וּבַזְּמַן הַזֶּה שֶׁהִיא עוֹמֶדֶת לִשְׂרֵפָה מִפְּנֵי הַטֻּמְאָה יֵשׁ לוֹ לְהַפְרִישׁ כָּל שֶׁהוּא לְכַתְּחִלָּה:
There is no minimum requirement for the great terumah according to Scriptural Law, as [implied by Deuteronomy 18:4]: "The first of your grain," i.e., even the slightest amount. Even one kernel of grain fulfills the requirement for the entire grain heap. Idealy, one should separate only according to the measures specified by our Sages. In the present age, when [the terumah] will be burnt because of impurity, a person may separate even the smallest amount as an initial and prefatory measure.
