谷朊粉对冻干枣粉抑制吸湿作用研究  

Study of wheat gluten on hygroscopicity inhibition of freeze-dried jujube powder

作　　者：古丽米热·如苏力 李莎[1] 王昆银 李斌[1] 李晶[1] GULIMIRE Ru-Su-Li;LI Sha;WANG Kun-Yin;LI Bin;LI Jing(College of Food Science and Technology,Huazhong Agricultural University,Wuhan 430070,China)

机构地区：[1]华中农业大学食品科学技术学院,武汉430070

出　　处：《食品安全质量检测学报》2022年第11期3602-3610,共9页Journal of Food Safety and Quality

基　　金：国家自然科学基金面上项目(31871844)。

摘　　要：目的研究谷朊粉对冻干枣粉吸湿特性的影响。方法将谷朊粉与枣浆按不同比例均匀混合,真空冷冻干燥后粉粹,过60目筛制备不同配比的冻干枣粉,通过吸湿动力学曲线、吸湿等温线、接触角、低场核磁共振、宏观和扫描电镜图片等分析方法评价其湿特性。结果谷朊粉显著降低了冻干枣粉的平衡含水率。吸湿等温结果表明,红枣与谷朊粉为10:0、7:3、1:1、3:7(m:m)样品的吸湿等温类型属“J”型增长,而0:10(m:m)样品的属“S”型增长,表明谷朊粉的添加并未改变冻干枣粉吸湿等温类型;接触角随着谷朊粉的添加量的增加,其值从31.22°增大到80.33°,说明谷朊粉可以减弱冻干枣粉的表面润湿性。从宏观和扫描电镜图中可知,冻干枣粉结块现象随着谷朊粉的添加量的增大而逐渐减轻。低场核磁共振结果显示,谷朊粉降低自由水的含量,减少水分向高自由度方向的迁移程度。结论一定量的谷朊粉能够有效抑制冻干枣粉的吸湿,从而缓解结块的发生,保持流动性和分散性,进而提高冻干枣粉的品质。Objective To study the effect of wheat gluten on hygroscopicity of freeze-dried jujube powder.Methods The wheat gluten and jujube pulp were mixed evenly in different proportions.Powder after vacuum freeze-drying,jujube powder with different proportions was prepared by passing through a 60-mesh sieve.The hygroscopicity were evaluated by analysis methods such as hygroscopic kinetic curve,hygroscopic isotherm,contact angle,low-field nuclear magnetic resonance,macroscopic and scanning electron microscope images,etc.Results Wheat gluten significantly reduced the equilibrium moisture content of freeze-dried jujube powder.Hygroscopic isotherm results showed that the hygroscopic isotherm type of jujube and wheat gluten at 10:0,7:3,1:1 and 3:7(m:m)samples was“J”type growth,while the hygroscopic isotherm type of 0:10(m:m)sample was“S”type growth.Thus,the addition of wheat gluten did not change the hygroscopic isotherm type of freeze-dried jujube powder;the contact angle increased from 31.22°to 80.33°with the addition of wheat gluten,indicating that wheat gluten could reduce the surface wettability of freeze-dried jujube powder.Macroscopical and scanning electron microscopy images showed that the aggregates of freeze-dried jujube powder was gradually reduced with the increase amount of wheat gluten.Low-field nuclear magnetic resonance results showed that wheat gluten reduced the content of free water and inhibited the water to migrate towards a high degree of freedom.Conclusion A certain amount of wheat gluten can inhibit the hygroscopicity of freeze-dried jujube powder effectively,thereby alleviating the occurrence of caking,maintaining its fluidity and dispersity,improved the quality of freeze-dried jujube powder.

关 键 词：枣粉 谷朊粉 水分迁移 吸湿等温线 

分 类 号：TS255.4[轻工技术与工程—农产品加工及贮藏工程]