不同粒径米糠对面团特性及饼干品质的影响

富含营养的米糠添加到饼干中成为营养饼干开发的重要方向。为评价不同粒径米糠对面团特性及饼干品质的影响，该研究制备了4种不同粒径（50、100、150、200目）米糠原料，探究了其对面粉粉质特性、面团流变特性、饼干质构特性和感官品质影响，并从面筋蛋白巯基含量、谷蛋白大分子聚合物（Glutenin Macropolymer,GMP）含量和面团微观结构变化等角度初步分析了其影响机制。结果表明，随着米糠粒径的减小，面团的稳定时间、形成时间降低，粘弹性模量增大；减小米糠粒径后可提高饼干质构特性，表现为硬度和咀嚼性降低；200目米糠饼干的模糊数学感官评分最高，达77.02分。添加米糠后，面筋蛋白巯基含量随米糠粒径减小而逐渐增大，GMP含量则逐渐降低，面筋网络结构逐渐弱化，表明降低米糠粒径促进了面筋蛋白二硫键的断裂，GMP的解聚，以及面筋网络强度的降低，从而改善了米糠饼干品质。研究结果为推动米糠在饼干等焙烤食品中的应用提供了理论指导。

Effect of Different Particle Sizes of Rice Bran on Dough Characteristics and Biscuit Quality

The addition of rice bran to biscuits has become an important direction in the development of nutritious biscuits. In order to evaluate the effects of different particle sizes of rice bran on dough properties and biscuit quality, four different particle sizes (50 mesh, 100 mesh, 150 mesh, and 200 mesh) of rice bran were prepared in this study. The effects on farinograph properties, dough rheology, biscuit texture properties, and sensory quality were investigated. Moreover, the mechanisms of their effects on the sulfhydryl content of gluten, glutenin macropolymer (GMP) content, and microstructure of dough were also preliminarily analyzed. With the decrease in rice bran particle size, the stability and development time of dough decreased and the viscoelastic modulus increased. Reducing the particle size of rice bran improved the textural characteristics of the biscuits, which had a decrease in hardness and chewiness. The fuzzy mathematics sensory score of rice bran biscuits with 200 mesh reached the highest score of 77.02. After adding rice bran, the sulfhydryl contents of gluten gradually increased with the decrease in rice bran particle size, whereas the GMP content gradually decreased and the gluten network structure gradually weakened. This indicated that a smaller rice bran particle size promoted the breakage of gluten disulfide bonds, the depolymerization of GMP, and the decrease in gluten network strength, thus improving the quality of rice bran biscuits. The results of the study provide theoretical guidance to promote the application of rice bran in bakery products such as biscuits.