模拟反复冻融条件对蛋品质的影响

Effect of simulating the conditions of repeated freezing and thawing on egg quality

为了研究反复冻融条件对鸡蛋蛋品质的影响,试验选取生鲜鸡蛋50枚,10枚当日进行测定,其中5枚用于测定常规鸡蛋品质指标,另5枚煮熟后用于测定熟鸡蛋的质构指标,此为新鲜鸡蛋组;其余随机分为4组,其中-18℃冻2 h后再于4℃融24 h的为冻融1组,此后再-18℃冻2 h后再于4℃融24 h(冻融2次)的为冻融2组,冻融3组反复冻融3次,冻融4组反复冻融4次,每组随机抽取10枚,其中5枚用于测定常规鸡蛋品质指标,另5枚煮熟后用于测定熟鸡蛋的质构指标。结果表明:随着反复冻融次数的增加,鸡蛋品质下降,新鲜度下降;经过冻融处理后,熟蛋黄硬度、弹性、咀嚼性和回复性都呈增加趋势;熟蛋白弹性、咀嚼性随着冻融次数的增加呈现下降趋势,经过反复冻融处理后的鸡蛋就形成了市场上所谓的"橡皮蛋"。

To study the effects of the conditions of repeated freezing and thawing on the egg quality of hen egg, fifty fresh hen eggs were selected in the test. Ten fresh eggs were selected as a fresh egg group, thereinto, five eggs in the group were used for the determination of quality indexes of conventional eggs, and the other five fresh eggs were used for the determination of textural indicators of the cooked eggs. The rest were ran- domly divided into four groups, thereinto, the freezing - thawing group 1 was treated with freezing at - 18 ~C for 2 h after and thawing at 4 ~C for 24 h; the freezing - thawing group 2 was treated with freezing at - 18 ~C for 2 h after and thawing at 4 ~C for 24 h again （ freezing and tha- wing for twice） ; the freezing and thawing group 3 was treated with the repeated freezing and thawing for three times; the freezing and thawing group 4 was treated with the repeated freezing and thawing for four times. The ten eggs in each group were randomly selected, thereinto, five eggs in the each group were used for the determination of quality indexes of conventional eggs, and the other five fresh eggs were used for the de- termination of textural indicators of the cooked eggs after cooking. The results showed that with the increase of the times of repeated freezing and thawing, the egg quality and freshness of hen egg decreased. The hardness, elasticity, chewiness and reversibility of the cooked yolk presented an increasing.trend after the treatment of freezing and thawing. The elasticity and chewiness of the cooked protein showed a decreasing trend with the increase of the times of repeated freezing and thawing. The hen eggs treated with the repeated freezing and thawing reformed the so - called rubber eggs in the market.