Zakat al-Fitr continued to be given during the time of the Messenger of Allah ﷺ as a saa of dates, barley, dried curd, or raisins.
حدثنا يحيى عن داود يعني ابن قيس عن عياض
لم تزل تخرج زكاة الفطر على عهد رسول الله ﷺ صاع من تمر أو شعير أو أقط أو زبيب
Its isnad is sahih. Iyad is Ibn Hilal, a trustworthy narrator mentioned previously, and Dawud bin Qays al-Farra is also trustworthy. The hadith appears in Bukhari 3/371 no. 1506, in the Book of zakat, Chapter on Sadaqat al-Fitr, and in Muslim similarly 2/678 no. 985, and in Tirmidhi 3/50 no. 673 with similar wording, where he said, hasan sahih, and in Nasai 5/47 no. 2500.