Fractionation of soybean meal, cottonseed meal and wheat middlings using combination of sieving and air classification

In earlier studies, the combination of sieving and air classification was found to be effective in separating fiber from distillers dried grains with soluble (DDGS) and corn flour. The objective of this study was to evaluate the combination of sieving and air classification for fiber separation from soybean meal (SBM), cottonseed meal (CSM) and wheat middlings (WM). Feeds were sieved into size fractions and the size fractions were then air classified into lighter and heavier fractions. The product obtained by combining the lighter fractions is called “fiber co-product” and the remaining material is called “enhanced feed”. The combination of sieving and air classification increased protein content most for SBM (from 539 g/kg to 553–557 g/kg), followed by CSM (from 499 g/kg to 521–527 g/kg) and WM (from 192 g/kg to 194–201 g/kg). Fiber separation was more effective for SBM compared to CSM and WM.