Randıman, diğer bir deyişle üretimde verimlilik, değirmenciliğin son derece önemli ve aynı zamanda tartışmalı konularından birisidir. Temizlenmiş buğdayın un üretimi için kullanılan yüzdelik dilimi olarak açıklanabilecek randıman, doğrudan üretim miktarına etki etken bir süreçtir. Bu yüzden değirmenciler, buğdaydan mümkün olan en yüksek düzeyde faydalanmak ister.  

Flour yield is one of the most important and controversial topics in the milling industry. Yield, which can be defined as the percentile of the wheat amount used for flour, is a process that directly affects the production amount. Thus, millers want to benefit from the wheat with the highest possible level. However; this process affects quality as well. Because yield can increase the ash amount in the flour and this affcets the four quality adversely. Thus, many methods and technologies are used in order both to maintain a specific standard for quality and increase the yield rate. However; despite all these, millers cannot reach the required yield and flour quality most of the times due to various reasons. Even though it seems possible to reach a yield rate of 80-85% in theory, it can be achieved only with a rate of 60-75% in practice.