Identification of superoxide dismutase as a novel biomarker for the differentiation of fresh and frozen-thawed goat meat

Abstract

Labeling defrosted meat as fresh is a prevalent fraudulent practice in the meat supply chain. Among various analytical techniques for distinguishing between fresh and frozen-thawed meat, enzyme biomarker-based methods are crucial and reliable. This study identifies superoxide dismutase (SOD) as a new biomarker enzyme for differentiating fresh and frozen-thawed goat meat. A fourfold increase in SOD enzyme activity was observed in frozen-thawed goat meat due to muscle injury from freezing and thawing. Meat express juice (MEJ) was prepared by dipping method to minimize false positives. SDS-PAGE analysis of MEJ showed thicker bands for frozen-thawed samples, indicating higher protein content of MEJ from the frozen-thawed sample. DEAE Sephacel ion-exchange chromatography was employed to purify MEJ and fractions with high protein concentrations were analysed by SDS-PAGE and dot blot assay to confirm the presence of SOD. This study establishes SOD as a reliable biomarker for distinguishing fresh from frozen-thawed goat meat.