Relationship of Grain Starch with Processing Quality in Different Quality Types of Wheat

The relationship between starch components and processing quality indices was studied.The results showed that grain starch content was negatively correlated with quality indices such as falling number,wet gluten content,sedimentation value,dough development time and stability time.Grain protein content was significantly positively correlated with falling number,wet gluten content,sedimentation value,dough development time and stability time.So strong-gluten and medium-gluten wheat should limit starch content in grains to some extent.But weak-gluten wheat should have high grain starch content.Variance ranges of peak viscosity and pasting temperature were the greatest in seven pasting parameters.Starch and amylose contents were negatively linearly related to protein content,wet gluten content and stability time.Starch indices of wheat with good quality were proposed according to national standard of protein and wet gluten contents,and stability time(GB/T17892-1999、17893-1999).For strong-gluten wheat with good quality(first-class),starch content(SC) should be less than 68.8%,and amylose content(AC) should be less than 13.5%.For strong-gluten wheat with good quality(second-class),SC should be less than(71.1%), and AC should be less than 14.5%.For weak-gluten wheat with good quality,SC should be more than 78.5%,and AC should be more than 17.3%.