冻融对冷冻新疆馕坯及其品质的影响  

Effects of Freezing-Thawing Cycles on Quality of Frozen Semifinished and Finished Xinjiang Naan

作　　者：冯亚倩 李文钊[1] 田霄翔 王梦妍 阮美娟[1] FENG Ya-qian;LI Wen-zhao;TIAN Xiao-xiang;WANG Meng-yan;RUAN Mei-juan(College of Food Science and Engineering,Tianjin University of Science&Technology,Tianjin 300457,China)

机构地区：[1]天津科技大学食品科学与工程学院,天津300457

出　　处：《食品研究与开发》2023年第11期29-35,共7页Food Research and Development

摘　　要：为探究储运过程中冻融频次对冷冻新疆馕坯品质的影响,模拟设计冻融频次试验(0~4次),利用低场核磁共振仪、流变仪、扫描电子显微镜与傅里叶变换红外光谱仪等检测、分析冷冻新疆馕坯的水分结合状态、流变学特性、微观结构及蛋白质二级结构等的变化,并通过烘焙试验综合评价冷冻新疆馕坯的感官品质,考察其烘焙特性。结果表明:随着冻融频次增加,冷冻新疆馕坯拉伸强度与拉伸距离明显降低;其流变学特性(弹性模量G’与黏性模量G’’)呈明显下降趋势;其强结合水不断流失,弱结合水先下降后上升又下降,自由水略有增加;内部微观结构观察显示,冷冻新疆馕坯出现明显的空洞与凹痕;蛋白质内部β-折叠含量降低,β-转角含量增加,有序的蛋白质二级结构变得松散、无序;同时,反复冻融也会导致冷冻新疆馕坯烘焙特性降幅增大,包括馕坯比容降低、硬度升高、综合感官评分降低等,储运过程中冷冻新疆馕坯冻融频次不宜超过4次。The effect of freezing-thawing cycles(0-4)on the quality of frozen semifinished Xinjiang naan during storage and transportation was studied.The changes of moisture migration state,rheological properties,microstructure,and protein secondary structure of frozen semifinished Xinjiang naan in freezing-thawing cycles were measured by a low-field nuclear magnetic resonance instrument,a rheometer,a scanning electron microscope,and a Fourier infrared spectrometer,respectively.The sensory quality of Xinjiang naan was evaluated through baking experiments,on the basis of which the backing characteristics were analyzed.The results showed that with the increase in freezing-thawing cycles,the tensile strength,tensile distance,and rheologicalproperties(elastic modulus G'and viscous modulus G'')of frozen semifinished Xinjiang naan decreased significantly.The strongly bound water continuously decreased;the weakly bound water presented a decreasing-increasing-decreasing trend;and the free water increased slightly.As the freezing-thawing cycles increased,obvious voids and dents appeared in the frozen semifinished Xinjiang naan,and the protein secondary structure became loose and disordered with decreasedβ-sheets and increasedβ-turns.Moreover,repeated freezing-thawing led to a decrease in the specific volume,an increase in hardness,and a decrease in comprehensive sensory score.The results suggested that the freezing-thawing should not exceed 4 cycles for the frozen semifinished Xinjiang naan in storage and transportation.

关 键 词：储运 冻融频次 冷冻新疆馕坯 烘焙特性 感官品质 

分 类 号：TS213.2[轻工技术与工程—粮食、油脂及植物蛋白工程]