Sahih Bukhari
Food, Meals
Volume: 007 / Book Number: 065 / Hadith Number: 321
Narrated Abu Hazim:
that he asked Sahl, "Did you use white flour during the lifetime of the Prophet ?" Sahl replied, "No. Hazim asked, "Did you use to sift barley flour?" He said, "No, but we used to blow off the husk (of the barley)."