Effects of Ozone Water Rinsing on the Qualities and Oxidation of Surimi Myofibrillar Proteins of Spanish Mackerel Surimi

Spanish mackerel surimi was rinsed by different concentrations(0,2,4,6,8,and 10 mg/L)of ozone water to investigate its influences on sensory qualities of surimi and oxidation of surimi myofibrillar proteins. The results showed that the whiteness of surimi increased and the electronic nose responses of fishy smell obviously reduced with the increasing concentrations of ozone water after rinsing. The electronic nose responses of fishy smell in surimi,including aromatic,ammonia,short-chain alkane,methyl and organic sulfur compounds,obviously reduced after rinsing by ozone water. The result of GC-MS demonstrated that the contents of volatile compounds in surimi rinsed by ozone water,such as aldehydes,alcohols,olefins,thioethers,alkanes compounds,decreased significantly(P<0.05). The carbonyl contents of myofibrillar proteins in rinsed surimi escalated,while the contents of total sulfhydryl groups decreased remarkably,with the increasing concentrations of ozone water. The Raman spectroscopy indicated that the structure and conformation of myofibrillar proteins suffered changes after rinsing,including the decreasing of a-helical relative content,the increasing of β-turn,β-sheet,random coil content. And the tryptophan and tyrosine amino acid residues exposed to the polaring environment. SDS-PAGE showed that the cross-link and aggregation of myofibrillar proteins occurred in the rinsed surimi. The above results would indicate that ozone water rinsing could improve the whiteness and flavor of Spanish mackerel surimi,and also cause oxidation of the myofibrillar protein,which led to the changes of protein structural and conformational properties.