蛋黄与蛋清对特二粉面筋聚集特性的影响

Effects of egg yolk/egg white on the aggregation characteristics of second-grade wheat flour

目的:蛋黄与蛋清添加到小麦粉中以期为加工与改良特色面制食品提供数据支撑。方法:以特二粉及鸡蛋为原料,利用面筋聚集仪研究特二粉在添加蛋黄与蛋清时面筋聚集特性的变化,并分析了聚集过程中面团显微结构和淀粉颗粒度的变化。结果:蛋黄添加量为5 mL时峰值扭矩(BEM)下降了9.5 BU,下降比例为19.39%;蛋清添加量为3 mL时BEM增加了4.08%,达到最大值;蛋清更有利于峰值扭矩的维持。蛋黄添加量为2 mL时峰值时间(PMT)下降了18.56%,达到最低值;蛋清添加量为1 mL时PMT上升了29.52%,达到最大值;表明添加蛋黄与蛋清对PMT的影响作用相反。随蛋黄添加量的增加S 3值占总能量的比例从81%增加到96%;而蛋清随添加量的增加S 3值占总能量的比例从43%波动增加到52%。结论:蛋黄与蛋清对面筋聚集特性的影响作用效果不一致,蛋黄与蛋清均显著改变面筋聚集能量的分布状态,蛋黄可降低面筋网络结构的连接力,使面筋蛋白网络结构断裂而分布更加均匀;而蛋清对面筋蛋白网络连接有促进作用,且蛋清对淀粉颗粒具有一定的保护作用。

Objective:Egg yolk and egg white were added to wheat flour to provide data support for the processing and improvement of characteristic flour food.Methods:The present study aims to disclose the influence of egg yolk and white on the aggregation characteristics of gluten in wheat flour using a special gluten aggregation instrument,as well as second-grade wheat flour and eggs as materials.Moreover,the dough microstructure and starch particle size during the aggregation process were also analyzed.Results:The results showed that BEM dropped 9.5 BU(i.e.,19.39%)with 5 mL egg yolk added.However,the BEM increased by 4.08%to the peak with the addition of 3 mL egg white,indicating that egg white is helpful to the maintenance of BEM.The supplement of 2 mL egg yolk or 1 mL egg white resulted in the 18.56%decrease(to the min.value)or the 29.52%increase(to the max.value)of PMT,which suggested that yolk and white may exert the opposite effect on PMT.Interestingly,with the addition of yolk and white,the ratios of S 3/total energy scaled up from 81%and 43%to 96%and 52%,respectively.Such a fact indicated that both yolk and white from egg significantly change the distribution of gluten aggregation energy.Conclusion:Taken together,yolk and white have varied roles in regulating gluten aggregation properties.To be noted,egg yolk inhibited the linking strength of the gluten network,giving rise to its breakage and a more even distribution;while egg white promoted such connection,and protected the starch particles.Our data will technically support the improvement of quality for flour-associated food.