不同品质类型小麦籽粒淀粉与加工品质的关系

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

以江苏省具有代表性的三个不同品质类型小麦品种为材料,分析了籽粒淀粉和加工品质的关系,以明确淀粉对小麦加工品质的作用以及优质小麦的具体淀粉指标。结果表明,淀粉含量与降落值、湿面筋含量、沉淀值、面团形成时间、稳定时间等加工品质指标呈显著负相关,而蛋白质含量与上述指标呈极显著正相关,说明中、强筋小麦不宜追求过高的淀粉含量,而弱筋小麦则应提高淀粉含量。在淀粉粘度特性7个参数中,以峰值粘度和糊化温度变异度最大。总淀粉和直链淀粉含量与蛋白质含量、湿面筋含量、面团稳定时间均呈显著的线性负相关关系。以优质专用小麦符合国标(GB/T 17892-1999、17893-1999)蛋白质含量、湿面筋含量、面团稳定时间为条件的淀粉指标被初步提出:一等强筋小麦籽粒总淀粉含量应≤68.8%,直链淀粉含量应≤13.5%;二等优质强筋小麦籽粒总淀粉含量应≤71.1%,直链淀粉含量应≤14.5%;优质弱筋小麦籽粒总淀粉含量应≥78.5%,直链淀粉含量应≥17.3%。

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/T/7892-1999,17893-1999）. 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%.