【摘要】 新疆牛肉品质优良，是新疆著名的畜产品资源之一。为了实现新疆牛肉新鲜度的实时监测，本文以羧甲基纤维素、聚乙烯醇为原料，利用物理冻融法制备水凝胶，并对水凝胶的物理特性进行表征；进一步筛选紫苏色素提取物为最佳显色色素制备智能指示标签，同时研究其对新疆牛肉冷藏过程中新鲜度的智能指示效果。结果表明：聚乙烯醇与羧甲基纤维素最佳比例为4:3，经过3次冻融循环制备的水凝胶具有良好的吸水能力(2937.39%)、色素包埋率(24.62%)、孔隙率(97.71%)、硬度、弹性、胶黏性和疏松多孔的网状微观结构。牛肉贮藏第2 d指示标签的色差值(ΔE)为10.2，第18 dΔE为26.5，大于人眼可分辨的颜色差异阈值(ΔE=3.5)。指示标签ΔE与牛肉新鲜度指标pH、挥发性盐基氮含量显著相关(P<0.01)，表明该智能指示标签可以准确、灵敏地指示新疆牛肉冷藏过程中新鲜度的变化。更多还原

【Abstract】 Xinjiang beef has high quality and is one of the famous livestock products resources in Xinjiang.In order to achieve the real-time monitoring of beef freshness,hydrogels were prepared by physical freeze-thaw method using carboxymethyl cellulose and polyvinyl alcohol as raw materials.The physical characteristics of hydrogels were also characterized.Furthermore,an intelligent indicator label was made using Perilla leaf pigment extract as the optimum color pigment,and its intelligent indication effect on the freshness of Xinjiang beef during cold storage was studied.The result showed that the optimum ratio of polyvinyl alcohol to carboxymethyl cellulose was 4:3,and the hydrogel prepared by three freeze-thaw cycles had good water absorption ability(2937.39%),pigment inclusion rate(24.62%),porosity(97.71%),hardness,elasticity,glue viscosity and loose porous network microstructure.The color difference value(ΔE) of indicator label on the second day was 10.2,and which was 26.5 on 18th day.This color change was larger than the threshold of color difference discerned by human eyes(ΔE=3.5).Correlation analysis showed that the ΔE values of indicating label were significantly correlated with pH and volatile base nitrogen contents of beef(P<0.01),which indicated that the intelligent indicating label could accurately and sensitively indicate the changes of freshness of Xinjiang beef during cold storage.更多还原