冰温结合气调贮藏对新鲜牛肉的保鲜研究

Preservation of Fresh Beef with Controlled Freezing-point and Modified Atmosphere Packaging Combination

研究了冰点调节剂食盐和蔗糖对新鲜牛肉冰点的影响;通过研究新鲜牛肉贮藏过程中色差值、菌落总数、pH值、挥发性盐基氮、液汁流失率等指标的变化情况,分析比较了冰温条件下4种气调包装与真空包装、空气包装对牛肉品质的影响。结果显示,当用食盐(添加量为1%)、蔗糖(添加量为0.6%)对牛肉进行调味时,冰温带由0～-0.76℃拓宽至0～-4.56℃,更有利于冰温贮藏温度的控制;冰温气调对新鲜牛肉的保鲜作用明显,第12天时C组样品色泽保持较好,TVB.N为6.68 mg/(100g),菌落总数为3.97 log cfu/g,在国家一级鲜肉标准范围内;第32天时,TVB.N为14.36 mg/(100g),菌落总数为5.38 log cfu/g,未超过相关限量规定,而真空组和空气组均已腐败,说明冰温与气调包装结合可起到协同保鲜作用,更有利于延长新鲜牛肉的货架期。

The effects of freezing point modifier （salt or sucrose） on the freezing point of fresh beef were investigated. Chromatic aberration, total bacterial counts, pH, TVB-N and liquid loss of the beef during storage were monitored. The quality of fresh beef under modified atmosphere packaging, vacuum packaging and air packaging stored at the tem- perature of controlled freezing point was analyzed and compared. The results showed that seasoned with 1% salt and 0.6% sucrose the ice temperature scope is broaden from 0 - -0.76 ℃ to 0 - -4.56 ℃ ; CF and MAP storage exhibit a significant fresh-keeping effect on the fresh beef; after stored for 12 days, the group C still remains normal color; TVB-N and total bacterial counts are 6.68 mg/（100g） and 3.97 log cfu/g, which are still in the range of first class fresh meat of national primary standard; after stored for 32 days, TVB-N and total bacterial counts are 14.36 rag/ （100g） and 5.38 log cfu/g, which are still in the acceptable range. In contrast, samples in vacuum packaging and air packaging are spoiled. Therefore, the combined CF and MAP method has a synergistic and beneficial effect on the preservation of fresh beef and can extend the shelf life of fresh beef.