From Sahih Bukhari (Hadith 5413):
Narrated Abu Hazim:I asked Sahl bin Sa`d, "Did Allah's Messenger (ﷺ) ever eat white flour?" Sahl said, "Allah's Messenger (ﷺ) never saw white flour since Allah sent him as an Apostle till He took him unto Him." I asked, "Did the people have (use) sieves during the lifetime of Allah's Messenger (ﷺ)?" Sahl said, "Allah's Messenger (ﷺ) never saw (used) a sieve since Allah sent him as an Apostle until He took him unto Him," I said, "How could you eat barley unsifted?" he said, "We used to grind it and then blow off its husk, and after the husk flew away, we used to prepare the dough (bake) and eat it
Reference: Bukhari 5413