Seasonal variation in the nutrient composition of mussels (Mytilus galloprovincialis) from farms in Boka Kotorska Bay, Southern Adriatic Sea

Abstract

Seasonal variation occurring in all seasons in one year in the nutrient composition of Mytilus galloprovincialis, cultivated in Boka Kotorska Bay, Montenegro, was investigated in this study. Biometric parameters, meat yield, condition index, proximate composition, minerals, as well as the lipid and fatty acid compositions of mussels were analyzed. Most significant factors determining these parameters were temperature, food amount and gametogenesis The biometric parameters showed no significant differences during the sampling period. In the spring, meat yields and mussel condition index increased at significant levels. Low values od meat yield and condition index during cold months has been a result of food shortage and reproductive cycle, when mussels use carbohydrates and protein reserves. The highest amount of protein was detected in mussels harvested in August (10.76%), while the highest amount of lipids was recorded in the winter months (2.11%). Fatty acid profiles revealed the predominance of polyunsaturated fatty acids (PUFA), followed by saturated (SFAs) and monounsaturated (MUFAs) fatty acids. Docosahexaenoic acid and eicosapentaenoic acid were the most abundant PUFA. The concentration of metals found in mussels from the study area is within the range of mean values reported in the literature. Our results indicate that the best period for mussels harvesting were during the spring and summer (April and August), opposite the winter months when the mussels were not favorable for harvesting.