超声波解冻对壳聚糖涂膜罗非鱼片的水分分布及品质相关性研究

The relationship between water distribution and quality of tilapia fillets with chitosan film as affected by different ultrasonic wave

为了研究不同超声波(200、250、300、350、400、450和500 W)对壳聚糖涂膜罗非鱼片水分分布与品质的关系,分别测定了解冻时间、解冻损失率、p H、TBA值、Ca2+-ATPase酶活性、弛豫时间T2,并分析探讨了水分分布与品质之间的相关性。结果表明,随着超声功率的增大(除300 W外),不易流动水含量A21增加(p<0.05)。p H、TBA值、Ca2+-ATPase酶活性与解冻时间、解冻损失率均有极显著的负相关关系(p<0.01),TBA值与不易流动水横向弛豫时间T22呈显著负相关关系(p<0.05)。7种超声功率中,450 W功率的超声波能较好的保持罗非鱼片的品质。与传统的流水解冻方法对比,其解冻时间、解冻损失率、Ca2+-ATPase酶活性等指标分别提升了62.67%、56.04%、23.42%。不易流动水横向弛豫时间T21最短,说明水分可移动性降低,提高了肌肉的保水性。因此,适当条件的超声波解冻罗非鱼片是可行的,且以450 W功率超声波解冻的效果更优,该结果将为超声波解冻方式在同类冻藏水产品中的应用提供参考。

In order to study the relationship between water distribution and quaiity of tilapia fillets affected by different ultrasonic wave（200,250,300,350,400,450 and 500 W ）, the thawing time, thawing loss, pH, TBA value, Ca^2＋ - ATPase activity ,transversal relaxation time T2 were measured, and the correlations between water distribution and quality were also analyzed.The results showed that with the increasing of the ultrasonic wave（ except the 300 W） ,the A21 of immobilized water increased pronouncedly （p 〈 0.05 ）.The pH, TBA value, Ca^2＋- ATPase activity had a significant negative correlation with thawing time and thawing loss（p 〈0.01 ）.Also there was a negative correlation between TBA value with T22 （p 〈0.05 ）. Compared with the control（ the running water thawing） ,the 450 W of ultrasonic wave was more suitable to maintain the quality of tilapia fillets through thawing time, thawing loss, Ca^2＋. ATPase activity improving respectively by 62.67%, 56.04%, 23.42% .The transverse relaxation time T21 of immobilized water was shortest,indicated that the mobility of water was lowered and the water hoiding capaeity was improved.So it is feasible to thaw the tilapia fillets by the appropriate conditions of ultrasonic and there is a better effect by the 450 W of ultrasonic wave.What＇ s more,the results will provide reference on application in the same kind of frozen aquatic products thawed by ultrasonic wave.