基于主成分分析的不同小麦品种大曲发酵动态品质评价

为了解小麦品质与大曲质量间的关系,该文测定了5个小麦品种的11个品质性状和大曲发酵中5个阶段的12个质量指标并进行了方差分析、回归分析和主成分分析。结果表明,不同小麦品种间在品质性状和大曲质量指标上存在显著或极显著差异。小麦籽粒容重、脂肪含量、吸水率、湿面筋含量、沉降值与大曲中蛋白增加含量呈极显著正相关;籽粒蛋白质含量与液化力、酯化力呈极显著负相关。多元逐步回归分析表明,大曲糖化力主要受原粮脂肪含量、沉降值和淀粉含量的影响,液化力受容重和淀粉含量的影响,发酵力受千粒重、容重和淀粉含量的影响,而酯化力受容重和淀粉含量的影响。前3个主成分因子的累积方差贡献率达74.57%,采用主成分综合得分筛选出淀粉含量和容重较高的“昌麦34”和“蜀麦691”适宜大曲生产。该研究明确了影响大曲的主要原粮品质性状并建立了新的综合得分评价原粮质量方法,为专用品种的选育和制曲工艺优化提供参考。

Comprehensive quality evaluation of Daqu of different wheat varieties based on principal components analysis

In terms of understanding the relationship between wheat quality and Daqu quality,eleven quality indexes and twelve Daqu indexes at five fermentation stages from five wheat varieties were evaluated by variance analysis,regression analysis and principal component analysis.The results indicated that significant differences(P<0.05)were observed in quality traits and Daqu quality indicators between different wheat varieties.The grain bulk density,fat content,absorption rate,wet gluten content,and sedimentation value were positively correlated with the increase of protein content in Daqu,while the grain protein content was negatively correlated with liquefaction power and esterification power.Multiple stepwise regression analysis showed that the saccharification power of Daqu was mainly affected by fat content,sedimentation value and starch content,the liquefaction power was affected by bulk density and starch content,the fermentation power was affected by 1000-grain weight,bulk density and starch content,and the esterification power was affected by bulk density and starch content.The cumulative variance contribution rate of the first three principal components was 74.57%.“Changmai 34”and“Shumai 691”,which were selected by principal component analysis with higher starch content and bulk density,were more suitable for Daqu production.The present results confirmed the wheat quality traits that affecting Daqu quality,established a new method to evaluate raw grain materials,and provided reference for specific end-use variety breeding and Daqu manufacturing process optimization.