PARTICLE SIZE DISTRIBUTION OF MILLED WHEAT AS AFFECTED BY BREAK ROLL DISPOSITION, GAP AND ENZYMATIC TEMPERING

The main objective of this study was to study the influence of break roll disposition, roller gap, and enzyme tempering on particle size distribution during wet milling of Australian commercial wheat (Triticum aestivum L.). Roller disposition was evaluated at two levels: dull-to-dull and dull-to-sharp. Roller gap was tested at three levels across three groups (G1, G2, and G3); (G1): B1, 0.3 mm; B2, 0.2 mm; B3,0.1 mm, (G2): B1,0.2 mm; B2, 0.1 mm; B3, 0.05 mm, (G3): B1,0.1 mm; B2, 0.05 mm; B3, 0.05 mm). Enzyme addition was tested at two levels: no enzymes and a combination of hemicellulase, xylanase, and fungal α-amylase. Results showed that break rolls parameters (roller gap and disposition), along with enzyme addition, significantly influenced particle size distribution. Predicting equations were developed to predict the optimum particle size distribution based on the best milling combinations. Enzymatic tempering proved an effective role in modifying both particle size and distribution. The best-fit equations, with R2 values ranging from 0.43 to 0.71, described the relationships among grain properties, roller position, roller gap, enzyme addition, and the resulting milling outcomes across different size fractions.