Effect of microwave thawing on the muscle quality and protein oxidation in Dosidicus gigas

The effects of various ways of thawing(4 ℃ refrigerator thawing and 500,700,900 W microwaves thawing)on the muscle quality and protein oxidation of frozen Dosidicus gigas were investigated. The changes of muscle quality were studied by measuring the thawing loss,cooking loss,color changes,texture profile analysis(TPA)and low field nuclear magnetic resonance(NMR). Factors reflecting proteins oxidation,such as the contents of carbonyl,total sulfhydryl,surface hydrophobicity and dityrosine,were also examined. The results indicated that the 500 W microwave thawing treatment could keep the whiteness,brightness and water holding capacity(WHC)well. It was also found that the elasticity and cohesion of samples was not significantly difference by all of the thawing methods(p>0.05),while the hardness,chewiness and resilience of samples by the 4 ℃ refrigerator thawing were significantly better than the microwave thawing method. The four thawing methods caused significantly different(p<0.05)carbonyl,total sulfhydryl,surface hydrophobicity and dityrosine contents,while the 500 W thawing treatment exerted the lowest carbonyl content and surface hydrophobicity contents and the highest total sulfhydryl. In conclusion,though the microwave thawing method could be more time-saving,but it was not very efficient to maintain the TPA of Dosidicus gigas. However,500 W microwave treatments were good for maintaining the WHC and delaying protein oxidation during thawing process.