预烘干对即食梅香黄鱼热杀菌前后色泽和质构特性的影响

Effects of Pre-drying Process on Color and Texture Characteristics of Ready-to-eat Fermented Yellow Croaker Before and After Thermal Sterilizing

为研究预烘干程度对即食梅香黄鱼热杀菌前后色泽和质构特性的影响,将腌制脱盐后的梅香黄鱼烘干至不同含水率后进行高温杀菌,以烘干前样品作为对照,测定了杀菌前后色差指标、质构指标和汁液流失率的变化。结果表明,烘干前不同部位的色差、质构指标均有显著差异（P〈0.05）;烘干过程中,总体来说,L^＊值下降、a^＊值和b^＊值升高,硬度、咀嚼性先增后减,弹性、内聚性和回复性均减小,剪切力、韧性均增大;杀菌后,总体来说,L^＊值下降、a^＊值和b^＊值均上升,硬度、弹性、内聚性、咀嚼性和回复性减小,剪切力、韧性增大;含水率为57%～54%时样品杀菌前后各色泽指标变化幅度相对较小,含水率为48%～45%时各质构指标变化幅度相对较小,含水率小于51%时汁液流失率相对较小。综上所述,预烘干对即食梅香黄鱼热杀菌前后色泽和质构特性有较大影响,适当的预烘干程度有利于减少产品杀菌后品质破坏的程度。综合色差、质构指标和汁液流失率来考虑,可选含水率51%作为适宜烘干程度。

In order to study the effects of pre-drying process on color and texture characteristics of ready-to-eat fermented yellow croaker before and after thermal sterilizing,the desalted samples were dried to different moisture content and then sterilized.The changes of chromatic attributes,texture attributes and liquid loss rate were investigated, with un-dried samples as control.Results showed as follows;The color and texture data of different sampling points had significant difference（P 〈0.05 ）.During the drying process,in general,the L＊ value decreased,a^＊ and b^＊ values both increased;the hardness and cohesiveness increased initially and decreased subsequently;springiness, cohesiveness and resilience decreased;the shear force and toughness increased.After thermal sterilizing,in general, the L^＊ value decreased,a^＊ and b^＊ values both increased;the hardness,springiness,cohesiveness,chewiness and resilience all decreased,while the shear force and toughness both increased.The color changed to a less extent for a range of moisture content between 57%and 54%,as the texture did when moisture content was between 48%and 45%.Besides,the samples had low liquid loss when moisture content was less than 51%.In conclusion,the pre-drying process has relatively great influence on the color and texture characteristics of ready-to-eat fermented yellow croaker before and after thermal sterilizing.Proper drying degree is beneficial to reduce the damage of thermal sterilizing. Considering the color,texture and liquid loss,drying to 51%moisture content is suitable.