Sahl b. Sa‘d said that God’s messenger never saw white bread from the time God commissioned him till God took him. He also said that God's messenger did not see a sieve from the time God commissioned him till God took him. He was asked how they could eat unsifted barley and replied that they ground it and blew it, and when some of it had flown away they moistened and ate what was left. Bukhari transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَن سهل بن سعد قَالَ: مَا رَأَى رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ النَّقِيَّ مِنْ حِينِ ابْتَعَثَهُ اللَّهُ حَتَّى قَبَضَهُ اللَّهُ وَقَالَ: مَا رَأَى رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مُنْخُلًا مِنْ حِين ابتعثهُ الله حَتَّى قبضَهُ قِيلَ: كَيْفَ كُنْتُمْ تَأْكُلُونَ الشَّعِيرَ غَيْرَ مَنْخُولٍ؟ قَالَ: كُنَّا نَطْحَنُهُ وَنَنْفُخُهُ فَيَطِيرُ مَا طَارَ وَمَا بَقِي ثريناه فأكلناه. رَوَاهُ البُخَارِيّ
sunnah.com