The Prophet Muhammad (peace be upon him) was ascetic in this world, eating the kind of food that poor people ate, along with whatever Allah had granted him from the world. In this hadith, Umm Ayman (may Allah be pleased with her)—who was the Prophet’s freed servant, caretaker, and the mother of Usama ibn Zaid—narrates that she sifted some flour, separating the fine white flour from the coarse bran and husk, and made a loaf of bread from it for the Prophet صلى الله عليه وسلم. He asked, “What is this?” She replied, “It is the food we make in our land.” Umm Ayman was from Abyssinia (Ethiopia). The Prophet صلى الله عليه وسلم then said, “Return what you sifted and knead it again.”

They had the stone grinders which were unable to grind the whole chaff, so they blew the ground flour & the bigger particles of chaff flew away, but the remaining flour still had some part of the chaff.

With the modern equipment & grinding machines today, we get the whole barley flour which is ultra-fine & almost all the chaff/husk is powdered, but if you still want to reduce it, you can sieve the flour & some larger particles of the chaff can be removed. Personally, I never do this, as the Barley’s chaff is insoluble fiber & it helps in bowel movement. Studies have shown that barley fiber (from chaff & bran) not only promotes gut motility but may help improve insulin sensitivity and cholesterol levels, particularly when consumed regularly as part of a whole-food diet.