不同盐含量对猪皮明胶凝胶品质特性和应力松弛的影响  

Effects of Salt Concentration on Gel Quality and Stress Relaxation of Pig Skin Gelatin

作　　者：苟浩 詹帅 徐万军 张雅琦 包玉龙 GOU Hao;ZHAN Shuai;XU Wanjun;ZHANG Yaqi;BAO Yulong(School of Food and Biological Engineering,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学食品与生物工程学院,江苏镇江212013

出　　处：《肉类研究》2024年第6期19-26,共8页Meat Research

基　　金：江苏大学高级人才基金资助项目(20JDG062)。

摘　　要：为探究不同浓度NaCl对明胶凝胶性质的影响,以猪皮明胶溶液(质量分数10%)为原料,分别在0.0、0.5、1.0 mol/L的NaCl浓度下制备明胶凝胶,分析凝胶化过程中三螺旋占比及凝胶的质构特性、持水性、水分分布状态和微观结构等理化指标,并对凝胶进行应力松弛特性分析。结果表明:随着NaCl浓度的增加,胶黏性、咀嚼性显著降低;NaCl浓度为1.0 mol/L时,明胶的硬度从对照组的3.15 kg下降到2.24 kg,NaCl浓度的增加会限制明胶溶液中三螺旋的形成;随着NaCl浓度的增加,明胶凝胶显示出更松散的网络结构,网络密度减小,孔径增大,持水性显著降低;不同盐含量下明胶凝胶的应力松弛行为差异较大,采用三元Maxwell模型拟合应力松弛测试结果时,1.0 mol/L NaCl组的明胶凝胶平衡弹性模量相比对照组降低53%;当采用CONTIN方法拟合应力松弛测试结果时,凝胶的弛豫峰分布重现性较差。综上,NaCl浓度的提高会减少明胶凝胶中三螺旋的形成,从而导致松散的网络结构,最终削弱明胶的机械性能和持水能力,明胶机械性能的下降与应力松弛测试结果相符。To investigate the effect of different concentrations of sodium chloride(NaCl) on the gel properties of gelatin,the triple helix content,texture properties,water-holding capacity,water distribution,microstructure and stress relaxation characteristics of gels of 10%(m/m) pig skin gelatin solution containing different concentrations(0.0,0.5 and 1.0 mol/L)of sodium chloride were analyzed.The results showed that with the increase in sodium chloride concentration,gumminess and chewiness was significantly reduced;the hardness of gelatin gel with 1.0 mol/L NaCl was 2.24 kg,lower than that(3.15 kg) of the control group.The increase in NaCl concentration limited the formation of triple helices in the gelatin solution;gelatine gels showed a looser network structure with increasing NaCl concentration,with reduced network density,increased pore size and a significant decrease in water-holding capacity.The stress relaxation behavior of gelatin gels with different salt concentrations was quite different.When the three-element Maxwell model was used to fit the stress relaxation test results,the equilibrium elastic modulus of gelatin gel with 1.0 mol/L NaCl was 53% lower than that of the control group.However,when the CONTIN model was used to fit the stress relaxation test results,the reproducibility of relaxation peak distribution of the gel was poor.In conclusion,the increase in NaCl reduced the formation of triple helix in gelatin gel,resulting in a loose network structure and ultimately weakening the mechanical properties and water retention capacity of gelatin gel.The decrease in mechanical properties of gelatin was consistent with the results of the stress relaxation test.

关 键 词：明胶 质构特性 应力松弛 三螺旋 持水性 

分 类 号：TS251.5[轻工技术与工程—农产品加工及贮藏工程]