常压和真空浓缩鸡汤的微冻贮藏特性

Quality Changes of Chicken Soup Concentrated under Atmospheric and Vacuum Conditions during Superchilling Storage

以4℃冷藏为对照,研究常压和真空浓缩处理后在-5.5℃微冻期间鸡汤贮藏特性的变化。结果表明:贮藏100 d,常压浓缩鸡汤的菌落总数增长几乎为零,而真空浓缩鸡汤菌落总数分别在微冻50 d、冷藏30 d后逐渐增加;常压浓缩鸡汤的亮度值(L*)下降幅度显著小于真空浓缩鸡汤(P<0.05),挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量和硫代巴比妥酸反应物(thiobarbituric acid reactive substances,TBARs)值变化幅度均小于真空浓缩鸡汤;常压浓缩鸡汤电泳条带变化没有真空浓缩明显。2种浓缩鸡汤在微冻贮藏期间的TVB-N含量和TBARs值显著低于冷藏期间(P<0.05);微冻真空浓缩鸡汤L*显著高于冷藏真空浓缩鸡汤(P<0.05);同时2种微冻浓缩鸡汤的电泳条带颜色较冷藏浓缩鸡汤深。说明常压浓缩和微冻贮藏有利于维持鸡汤色泽、抑制微生物繁殖以及减缓蛋白氧化和脂肪氧化。

This experiment aimed to study the changes in quality characteristics of chicken broth concentrated under atmospheric and vacuum conditions during superchilling storage(−5.5℃).Cold storage(4℃)was used as control.The results showed that after 100 days of storage,the total number of colonies in chicken soup concentrated under atmospheric conditions hardly grew,while the microbial load of vacuum concentrated chicken soup gradually increased starting from day 50 of superchilling and from day 30 day of refrigeration.The former displayed a significantly smaller decrease in brightness(L*)value and a smaller change in total volatile basic nitrogen(TVB-N)content and thiobarbituric acid reactive substances(TBARs)value,but exhibited less obvious changes in the protein electrophoresis bands.TVB-N and TBARs values of both concentrated chicken soups were significantly lower after superchilling storage than after refrigeration(P<0.05),and they showed darker protein bands in gel electrophoresis after superchilling storage than after refrigeration.These data showed that atmospheric concentration and superchilling storage were conducive to maintaining the color of chicken soup,inhibiting microbial reproduction,and repressing protein and fat oxidation.