Hadith 3307
Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates: I will always give in the form of a sa', just as we used to do in the blessed time of the Prophet (peace and blessings of Allah be upon him): a sa' of dates, a sa' of barley, a sa' of raisins, or a sa' of cheese. What he meant was that this was given as Sadaqat al-Fitr.