牛骨蛋白的酶法改性工艺优化及其结构和功能特性研究

Optimization of enzymatic modification process of bovine bone protein and study on its structure and functional properties

中文关键词:  牛骨蛋白  酶法改性  乳化性  工艺优化

英文关键词:bovine bone protein  enzymatic modification  emulsification  process optimization

中文摘要:

      目的 优化牛骨蛋白酶法改性工艺, 挖掘牛骨蛋白作为乳化剂稳定乳液的潜力。方法 采用碱性蛋白酶对牛骨蛋白进行改性, 以牛骨蛋白的乳化性为指标, 探究酶添加量、酶改性温度、体系pH和酶改性时间对牛骨蛋白乳化性的影响, 并通过响应面试验优化酶法改性工艺, 比较改性后牛骨蛋白的功能和结构变化。结果 牛骨蛋白的酶法改性最佳工艺为酶添加量2000 U/g、改性温度为55℃、pH 7.2、改性时间1.9 h, 此条件下牛骨蛋白的乳化活性、乳化稳定性、溶解度、持油性、持水性、起泡性和泡沫稳定性分别提高了53.85%、37.18%、51.43%、64.29%、50.16%、112.68%、167.22%; 紫外吸收光谱、荧光光谱表明改性后牛骨蛋白的内部基团暴露程度增加, 扫描电子显微镜结果显示, 改性后牛骨蛋白结构从有序的片状向不规则的纤维状转变。结论 牛骨蛋白在经过酶法改性后其乳化能力得到了明显提高, 为牛骨蛋白在食品乳液体系的应用提供一定参考和理论支持。

英文摘要:

      Objective To optimize the enzymatic modification process of bovine bone protein, and explore the potential of bovine bone protein as an emulsifier to stabilize the emulsion. Methods The emulsification of bovine bone protein was taken as the index, alkaline protease was used to modify bovine bone protein. The effects of enzyme addition, enzyme modification temperature, system pH and enzyme modification time on the emulsification of bovine bone protein were investigated. The enzymatic modification process was optimized by response surface test, and the functional and structural changes of bovine bone protein after modification were compared. Results The optimum enzymatic modification process of bovine bone protein was as follows: Enzyme addition amount 2000 U/g, modification temperature 55℃, pH 7.2, modification time 1.9 h. Under this condition, the emulsifying activity, emulsifying stability, solubility, oil holding capacity, water holding capacity, foaming capacity and foam stability of bovine bone protein were increased by 53.85%, 37.18%, 51.43%, 64.29%, 50.16%, 112.68% and 167.22%, respectively. Ultraviolet absorption spectra and fluorescence spectra showed that the internal group exposure of bovine bone protein increased after modification. Scanning electron microscopy results showed that the structure of bovine bone protein changed from ordered flake to irregular fibrous after modification. Conclusion The emulsifying ability of bovine bone protein has been significantly improved after enzymatic modification, which can provide certain references and theoretical supports for the application of bovine bone protein in food emulsion system.