不同液氮速冻温度下预制鸡排的品质变化

Quality Changes of Pre-made Chicken Chops under Different Liquid Nitrogen Flash-freezing Temperatures

为探究不同液氮速冻温度下预制鸡排的品质变化,该文采用液氮喷雾(-80、-100、-120℃)对鸡排进行速冻,同时以4℃保鲜冷藏和-18℃冰箱缓冻作对照,评价指标包括冷冻速率、感官评分、持水性、pH值、色泽、质构特性以及氧化指标测定。结果表明:液氮速冻工艺能显著缩短鸡排冷冻时间;液氮速冻-100℃鸡排的感官得分(70.83分)最接近4℃保鲜冷藏下的鸡排(84.00分),而液氮速冻-120℃会导致鸡排表面出现裂纹;液氮速冻能够较好地保持预制鸡排的持水性,液氮速冻-100℃鸡排的离心损失率为20.95%,而-18℃冰箱缓冻鸡排的离心损失率高达32.84%;各组别的pH值存在显著性差异(P<0.05),色泽指标无显著性差异(P>0.05),液氮速冻组各项质构指标总体优于-18℃冰箱缓冻;相比-18℃缓冻,液氮速冻-80℃和-100℃鸡排的丙二醛含量分别减少了22.54%和15.02%,谷胱甘肽过氧化物酶活分别提高了66.13%和132.58%。综上所述,相比-18℃缓冻,液氮速冻的鸡排保留有更好的食用品质,加工温度设置为-80℃至-100℃之间相对合适。

To explore the quality changes of pre-made chicken chops under different liquid nitrogen flash-freezing temperatures,liquid nitrogen spray(-80,-100,-120℃)was used to freeze chicken chops,whereas fresh storage at 4℃and slow freezing at 18℃were used as controls.The evaluation indicators included freezing speed,sensory score,water holding capacity,pH,color,texture and oxidation index.The results showed that treating chicken chops with liquid nitrogen flash-freezing considerably shortened the freezing time.The sensory score of chicken chops treated with liquid nitrogen flash-freezing at-100℃(70.83 points)was the closest to that of chicken chops refrigerated at 4℃(84.00 points),whereas treatment with liquid nitrogen flash-freezing at-120℃caused cracks on the surface of the chops.The water holding capacity of pre-made chicken chops can be effectively maintained by liquid nitrogen flash-freezing.The centrifugal loss rate of chicken chops treated with liquid nitrogen flash-freezing at-100℃was 20.95%,whereas that of chicken chops treated with slow freezing at-18℃was as high as 32.84%.A significant difference was detected in pH among the different groups(P<0.05),but not in color(P>0.05).The texture indices of the liquid nitrogen flash-freezing groups were generally superior to those of the-18℃slow-freezing group.Compared with slow freezing at-18℃,the malondialdehyde content of chicken chops treated with liquid nitrogen flash-freezing at-80 and-100℃decreased by 22.54%and 15.02%,respectively,whereas their glutathione peroxidase activity increased by 66.13%and 132.58%,respectively.In conclusion,compared with the slow freezing at-18℃,chicken chops treated with liquid nitrogen flash-freezing retained superior eating quality.It is recommended that the processing temperature be maintained between-80 and-100℃.