小麦面筋蛋白组分对挂糊油炸猪肉片外壳品质影响机理研究

The deep-fried battered (DFB) meat product having golden color and crisp crusts is one of the important traditional foods, and welcomed by consumers. Because of the lack of theoretical research, especially in effects of wheat gluten on the quality of DFB meat product, it is difficult to determine the parameters of wheat flour special for DFB meat product making, which seriously restricts the improvement of product quality. In this study, gluten protein from wheat flour is taken as the material, knowledge of cereal chemistry, rheology and physical properties of food would be the major theoretical basis, and the technology of segregation and recombination, gel electrophoresis，low field nuclear magnetic resonance, scanning electron microscope, Raman spectroscopy and texture analysis would be employed as the main analysis methods. The relationship between wheat gluten fractions (glutenin, gliadin, and their subfractions) and quality parameters (color, oil content, hardness, crispness, and microstructure) of crusts from DFB pork slices would be investigated. Simultaneously, the effect of gluten composition on quality of crusts will be analyzed. Subsequently, the changes of gluten molecular structure during making batter and frying will be explored. Additionally, the relationship between the quality of crusts from DFB pork slices and gluten structural changes would be found out. The mechanism of crust quality affected by gluten would be elucidated at molecular level. The present study would provide theoretical guide for quality control methods, production of flour and breeding of wheat special for DFB meat products.

挂糊油炸肉制品作为一类重要的传统食品，具有色泽金黄、外壳酥脆等特点，深受消费者的欢迎。由于理论研究特别是对糊中小麦面筋蛋白的理论研究缺乏而无法提出合适的挂糊油炸肉制品专用粉指标，严重制约了产品质量的提高。本项目以小麦面粉中的面筋蛋白为研究对象，以谷物化学、流变学、物性学等为主要理论依据，以分离重组、凝胶电泳、低场核磁共振、电镜扫描、拉曼光谱和质构检测等为主要技术手段，研究小麦面粉中麦谷蛋白及其组分、醇溶蛋白及其组分与挂糊油炸猪肉片外壳色度、吸油率、硬度、脆度、微观结构等主要品质参数间相关关系，分析面筋蛋白各组分对产品性质的影响规律；研究蛋白分子在制糊、油炸等加工过程中的变化与挂糊油炸猪肉片外壳品质间的关系，从分子层面探明蛋白分子对外壳品质的影响机理。该研究将为挂糊油炸肉制品专用粉生产、专用小麦育种和产品质量控制提供重要理论依据。

挂糊油炸肉制品作为一类重要的传统食品，具有色泽金黄、外壳酥脆等特点。由于理论研究特别是对糊中小麦面筋蛋白的理论研究缺乏而无法提出合适的挂糊油炸肉制品专用粉指标，严重制约了产品质量的提高。本项目基于此背景，以小麦面粉中的面筋蛋白为研究对象，以分离重组、凝胶电泳、电镜扫描和质构检测等为主要技术手段，研究了面筋蛋白、麦谷蛋白与醇溶蛋白、谷蛋白组分对糊粉功能特性及对挂糊油炸猪肉片外壳食用品质的影响规律；研究了蛋白分子、淀粉功能在制糊油炸加工过程中的变化与挂糊油炸猪肉片外壳品质间的关系。结果表明，面筋蛋白有利于提高糊粉的持水性和挂糊率，显著降低糊粉的峰值黏度、最终黏度、衰减值、谷值黏度和回生值。面筋蛋白含量增加会引起制品外壳L*值降低，a*值和b*值增大；而水分含量先升高又下降，脂肪含量先降低后升高；外壳硬度减少，脆性降低。随麦谷蛋白/醇溶蛋白比例的增加，糊粉的持水性、黏度和挂糊率均先增加后降低；制品外壳的L*值和a*值逐渐增大、b*值降低；脂肪含量先减少后增加；外壳硬度持续增加。HMW-GS/LMW-GS比例增加，降低了糊粉的持水率、黏度和挂糊率；影响了制品外壳的硬度和脆性。挂糊油炸导致总蛋白、清蛋白、球蛋白和醇溶蛋白含量下降；而谷蛋白在制糊中含量有所增加，初炸前60s变化不大，油炸60 s后逐渐下降；自由巯基含量减少、二硫键含量增加；蛋白质发生了聚集和解聚。随油炸温度的升高和油炸时间的延长，淀粉的溶解度和膨胀度均呈上升趋势，淀粉糊的凝沉稳定性得到改善；挂糊油炸猪肉片外壳的白度降低，红度和黄度增加；复炸时间较短，产品外壳白度较高，黄度较低；复炸时间过长，产品外壳红度过高。复炸时间延长，增大了外壳的硬度，改善了脆性和易碎性。此外，制品外壳的含油率与水分含量间具有负相关关系；可通过调节产品最终的水分而调节终产品的油脂含量。项目的实施对挂糊油炸肉制品专用粉生产、专用小麦育种和产品质量控制具有重要意义。