Proximate and fatty acid compositions of smoked underutilised South African mussel Choromytilus meridionalis

Abstract

Seafood is valued for its nutritional content; however, overfishing necessitates the focus on underutilised species to promote sustainable utilisation. We investigated the proximate and fatty acid compositions of hot-smoked Choromytilus meridionalis (black mussels) using AOAC International methods and gas chromatography. Lipid nutritional quality indices were calculated. Moisture content in mussels significantly (p < 0.05) decreased by 19% after hot smoking, whilst ash, protein, lipid, and carbohydrate contents increased by 98%, 42%, 46% and 49%, respectively. Hot smoking significantly increased the polyunsaturated (37.70 ± 1.06%) and omega-3 fatty acid (33.36 ± 1.23%) contents. Conversely, omega-6 and saturated fatty acids of hot-smoked mussels were significantly (p < 0.05) lower than those for raw mussels. The atherogenicity index and thrombogenicity index showed a significant reduction (p < 0.05), whilst the hypocholesterolaemic to hypercholesterolaemic ratio and the sum of EPA+DHA showed significant increases. This study shows that C. meridionalis is a valuable food with a high protein content and a well-balanced fatty acid composition, rich in omega-3 fatty acids. This study was the first to investigate the macronutrients of C. meridionalis.

Significance:

Choromytilus meridionalis is one of three bivalve species cultivated on a commercial scale along the West Coast of South Africa; however, it is underrealised as a commercial food product. The growing mussel industry has been considered a great potential for the alleviation of poverty, job creation, and food security. This research may provide mussel farmers, fish processing industries, and the community with information about processing opportunities using C. meridionalis. Successful product development may contribute to alleviating malnutrition and increasing food security.