高压湿热法改性玉米醇溶蛋白膜的工艺优化及性能分析

本研究采用高压湿热法对玉米醇溶蛋白膜进行改性处理，通过单因素实验和L₉（34）正交试验优化了高压湿热处理的工艺，并进行了性能研究。结果表明，最佳高压湿热处理条件为:成膜液体积9 mL、处理温度121 ℃、处理时间40 min。在此条件下玉米醇溶蛋白膜的吸水率低至11.35%±0.74%，浸水后透明度为181.30±3.29，相比未处理有显著改善（P<0.05）。同时，经过高压湿热改性后玉米醇溶蛋白膜的体外酶解抗性（14.92%±0.58%）和抗拉强度（16.51±2.13 MPa）明显增强。傅里叶红外光谱（FT-IR）分析表明，高压湿热改性导致玉米醇溶蛋白中β-转角结构向结构更加有序的无规则卷曲、β-折叠和α-螺旋结构转变。本文为高压湿热法辅助制备蛋白基高耐水性材料的开发提供理论基础。

Process Optimization and Performance Analysis of Modified Zein Film by High Pressure Heat-Moisture (HPHM) Treatment

In this study, zein films were modified by high pressure heat-moisture (HPHM) method and the technology of HPHM modification was optimized through single experiments and L₉(34) orthogonal tests, and the properties of zein film were studied. The optimal technology was as follows: Film-formation solution volume of 9 mL, treatment temperature of 112 ℃ and treatment time of 40 min. Under the optimal technology, the water absorption rate (WAR) and transparency of modified zein film was 11.35%±0.74% and 181.30±3.29, respectively, greatly improved than raw film (P<0.05). Meanwhile, the HPHM zein film exhibited obvious improved in vitro enzymatic hydrolysis resistance (14.92%±0.58%) and tensile strength (16.51±2.13 MPa). FTIR results also showed that the β-bend of zein molecule was converted to more ordered-arranged random coli, β-sheet and α-helix after HPHM modification. This study could provide essential foundations for manufacturing high-hydrophobic protein-based films assisted by HPHM modification.