Differential role of endogenous cathepsin and microorganism in texture softening of ice-stored @entity26584 ( XXXX ) fillets.

@entity13638 @entity4627 @entity26584 @entity2974
BACKGROUND: Texture deterioration often negatively affects sensory attributes and commercial values of ice-stored fish fillets. The mechanism of softening of fish fillets during chilling storage is not fully resolved. @entity26584 is a predominant freshwater fish species in China. The objective of the present study was to investigate the differential role of endogenous cathepsin and microorganisms in texture softening of ice-stored @entity26584 fillets. RESULTS: The fillets were immersed in either @entity4627 solution to reduce microbial activity or to @entity13638 solution to exclude cathepsin activity before ice-storage. Treatment with @entity4627 reduced microbial load of fillets below 2 log CFU g(-1) muscle during the entire storage period, and had no significant influence on the cathepsin activity and proteolysis. But the shear force of fillets treated with @entity4627 decreased by 66% after 21 days of storage. Meanwhile, treatment with @entity13638 inactivated cathepsin B and B+L but did not significantly affect the microbial growth of fillets. Compared to @entity4627 treatment, @entity13638 effectively alleviated softening and inhibited the increase in @entity2974 -soluble peptides during storage. CONCLUSION: This study demonstrated that proteolysis induced by endogenous cathepsins, rather than microorganisms, plays an important role in texture softening of ice-stored @entity26584 fillets.
