低场NMR研究冻融过程中羊肉持水力的变化  

Changes of Water Holding Capacity of Mutton during Freeze-thaw Cycles by a Low Field Nuclear Magnetic Resonance

作　　者：戚军[1,2] 高菲菲[1] 李春保[1] 徐幸莲[1] 周光宏[1] 杨培强 刘扬[4] 

机构地区：[1]南京农业大学国家肉品质量安全控制工程技术研究中心,江苏南京210095 [2]江苏迈斯克食品有限公司,江苏南京210001 [3]上海纽迈科技有限公司,上海200062 [4]镇江出入境检验检疫局,江苏镇江212008

出　　处：《江苏农业学报》2010年第3期617-622,共6页Jiangsu Journal of Agricultural Sciences

基　　金：国家引进国际先进农业科学技术(948)项目(2006G35);科技部中美国际科技合作项目(2009DFA31770)

摘　　要：为了探讨冻融过程中羊肉保水性的变化规律,用低场核磁共振(Nuclear magnetic resonance,NMR)技术研究了羊肉冻融过程中水的T2驰豫性质变化,同时用解冻汁液流失率、加压失水率、蒸煮损失率指标测定保水性变化。结果表明:随着冻融次数增加,解冻汁液流失率先显著增加,后保持较小变化,加压失水率和蒸煮损失率先显著下降再上升最后再显著下降。NMRT2驰豫测定结果显示,肌肉中有结合水、不易流动水和自由流动水3个组分,对应的横向弛豫时间分别是T2b、T21、T22,T21和冻融次数、蒸煮损失、加压失水率显著相关;T22与保水性的变化趋势一致。羊肉冻融后持水力显著下降,因此在流通过程中,尽可能避免冻融现象的出现,T21可以做为考察冻融后肉品质持水能力的一个重要指标。To discuss the change of the water holding capacity（WHC） and water mobility of mutton in the processing of freeze-thaw cycles,T2 relaxometry of water in lamb longissimus dorsi during freeze-thaw cycles were characterized using low-field nuclear magnetic resonance（NMR）,and the water thaw loss,pressing loss and cooking loss were determined as well.With the increasing of freeze-thawing cycles,thawing loss significantly increased and then kept the small change,pressing loss and cooking loss significantly decreased firstly,then increased and significantly decreased finally.Analysis of the NMR T2 relaxation data revealed the existence of three distinct water populations： T2b,T21 and T22,which corresponded to three states of water,i.e.hydration,immobilized and free water.A significant correlation was found between the T21 time constant and freeze-thaw cycle times,cooking loss and pressing loss.Change tendency of water holding capacity and T22 was coincident.After freeze-thawing,WHC of mutton significantly decreased.Therefore,the freeze-thaw of mutton was avoided to turn up as far as possible in circulation process,and T21 was an important index of WHC of meat after the processing of freeze-thaw cycles.

关 键 词：羊肉 冻融 持水能力 核磁共振 

分 类 号：TS251.53[轻工技术与工程—农产品加工及贮藏工程]