奥尔良鸡腿排冻藏期间的品质变化

Quality Changes of Orleans Chicken Leg Steak during Frozen Storage

以奥尔良鸡腿排为研究对象,每30 d对奥尔良鸡腿排的色泽、质构特性、剪切力、解冻损失率、蒸煮损失率、pH值、总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、硫代巴比妥酸反应物(thiobarbituric acid reactive substance,TBARs)值进行测定,并结合低场核磁共振(low field nuclear magnetic resonance,LF-NMR)技术对其水分状态进行测定,研究奥尔良鸡腿排在240 d冻藏期间的品质变化。结果表明:奥尔良鸡腿排的理化指标受冻藏时间影响显著(P<0.05),随着冻藏时间的延长,奥尔良鸡腿排的pH值不断增加,TBARs值呈上升趋势,TVB-N含量不断上升,菌落总数的变化趋势为先下降后上升;色泽指标中的亮度值及红度值呈降低趋势,而黄度值呈升高趋势;质构指标中的硬度、咀嚼性、黏结性和剪切力呈上升趋势,而弹性逐渐下降;蒸煮损失率和解冻损失率逐渐增大;横向弛豫时间T_(23)峰面积(自由水含量)减小,T_(21)峰面积(结合水含量)几乎不变,T_(22)峰面积(不易流动水含量)略有减小;磁共振成像结果表明,肉质表面氢质子发生明显迁移,与水分变化分析结果一致。

Changes in the quality of Orleans chicken leg steak were determined during 240 days of frozen storage. Color, textural properties, shear force, thawing loss, cooking loss, p H value, thiobarbituric acid reactive substance（TBARs） and total volatile basic nitrogen（TVB-N） values were measured every 30 days and moisture states were investigated by low-field nuclear magnetic resonance（NMR）. The results obtained showed that the physicochemical properties of chicken steak were significantly affected by storage time（P 〈 0.05）. The pH value, TBARs and TVB-N values decreased progressively decreased with storage time, and the total bacterial count rose initially and then fell. In addition, the brightness value and redness value dropped, whereas the yellowness value increased. The texture parameters such as hardness, chewiness, cohesiveness and shear force increased, while elasticity declined. Cooking loss and thawing loss ascended. The peak area of transverse relaxation time T23（free water content） fell, while the peak area of T21（bound water content） almost remained unchanged, and the peak area of T22（immobile water content） slightly dropped. Magnetic resonance imaging showed marked hydrogen proton migration on the meat surface, which was consistent with the changes in moisture state.