Effects of gluten protein fractions on dough property and products quality in common wheat

Chinese. 【目的】贮藏蛋白组成与组分含量显著影响食品加工品质，研究贮藏蛋白组分含量对加工品质的影响，指导小麦品质改良。【方法】选用近几年北方冬麦区育成的优质品种和高代品系及山东省主栽品种为材料，采用反相高效液相色谱（RP-HPLC）和凝胶色谱（SE-HPLC）方法对贮藏蛋白组分进行量化，并分析它们与面团流变学特性、面包、面条和馒头加工品质的关系。【结果】谷蛋白总量（Glu）、高分子量麦谷蛋白亚基（HMW-GS）含量和低分子量麦谷蛋白亚基（LMW-GS）含量与反映面筋强度的和面时间、稳定时间、拉伸面积和最大抗延阻力呈1%显著正相关（r = 0.61～0.83），与面包品质均呈显著正相关（r=0.34～0.85），而醇溶蛋白与谷蛋白含量比（Gli/Glu）与这些参数均呈显著负相关（r = -0.37～-0.85，P〈0.05）。SDS不溶性谷蛋白聚合体百分含量（%UPP）与面团稳定时间和最大抗延阻力呈对数关系，决定系数分别达0.84和0.86；与面包总分呈显著正相关（r=0.76，P＜0.001），决定系数为0.58。Glu、HMW-GS、LMW-GS和%UPP与面条的色泽、硬度、总分和馒头的光滑度呈5%显著负相关（r=-0.36～-0.63），而Gli/Glu与这些参数呈5%显著正相关（r=0.37～0.57）。醇溶蛋白总量及各组分含量与馒头的压缩张驰性呈1%显著正相关，与馒头的总评分呈显著负相关。【结论】贮藏蛋白组分含量对面团流变学特性和面包品质影响较大，当Glu和%UPP分别达到32.5 AU和48.9%时，面筋强度（稳定时间大于10.0 min）和面包品质较优，而对面条和馒头品质影响相对较小，且多为负向效应。

English. [Objective] The quantity of gluten protein fractions significantly influences wheat end-products quality, therefore, understanding of the effects of gluten protein fractions on products quality will be very useful for quality improvement. [ Method ] Totally, 43 wheat genotypes including newly released high quality cultivars and advanced lines in North China winter wheat region and leading cultivars in Shandong province, were grown in Jinan in 2005-2006. Their protein fractions were quantified by reversed-phase high-performance liquid chromatography （RP-HPLC） and size-exclusion high-performance liquid chromatography （SE-HPLC） methods to determine the relationship between protein fractions and dough properties and end-products. [ Result] The quantity of total glutenin, HMW-GS and LMW-GS were significantly and positively correlated with mixograph peak value, farinograph stability, extensograph extension area and maximum resistance, with r=0.61-0.83 （P〈0.001）, and they were significantly and positively associated with all bread quality parameters, with r=0.34-0.85 （P〈0.05 or P〈0.001）. But the ratio of Gli/Glu was significantly and negatively correlated with these parameters, with r=-0.37-0.85 （P〈0.05 or P〈0.001）. The percent of SDS-unextractable glutenin polymeric protein （%UPP） showed natural logarithm correlation with dough stability and maximum resistance, R. =0.84 and 0.86, respectively, %UPP was significantly and positively associated with bread total score, with r=-0.76 （P〈 0.001）. The quantity of total glutenin, HMW-GS, LMW-GS and %UPP were significantly and negatively correlated with noodle color, firmness, total score and steamed bread smoothness, with r=-0.36-0.63 （P〈0.05 or P〈0.001）, but the ratio of Gli/Glu was significantly and positively associated with these parameters, with r=-0.37-0.57 （P〈0.05）. The quantity of total gliadin was significantly and positively related with steamed bread stress relaxation, with r=0.54（P〈0.001）, but was significantly and negatively correlated with steamed bread total score, with r=-0.49（P 〈 0.001）.[ Conclusion ]Gluten protein fractions content had strong influence on dough properties and bread quality, but had slight effect on noodle quality and steamed bread, and were negatively correlated. When the quantity of total glutenin and %UPP were more than 32.5 AU and 48.9%, respectively, genotypes showed very good dough property with stability of ten minutes and bread quality.