A Critical Study on Seasonal Variation in Major Minerals (Ca, P, K, Mg) and Proximate Composition in Flesh of Mesopotamian Catfish (Silurus triostegus Heckel, 1843) from Turkey

In this study, the seasonal variation on selected major minerals (Ca, P, K, Mg) and proximate composition of Mesopotamian catfish (Silurus triostegus Heckel, 1843) were investigated. The mineral and proximate composition of fish varies greatly from one species and one individual to another depending on age, sex, environment, season, area of catch and processing method. Fish samples used in this research were obtained seasonally from Atatürk Dam Lake within the boundries of Turkey (37ºC45N’ latitude/38ºC17E’ longitude) via fishing. The mean value of Ca, P, K and Mg were determined as 92.59±9.81 µg/g, 1447.56±117.38 µg/g, 2762.50±418.00 µg/g and 227.26±39.79 µg/g (wet weight) respectively. The highest mineral contents were identified in summer. The highest crude protein was observed in autumn (18.88%) and the lowest in winter (16.88%).The average lipid content was identified between 4.22-6.56% and the highest value was observed in winter. The results showed significant differences between the four seasons (P<0.05) in major minerals and proximate composition. The results of this study showed that Mesopotamian catfish from Atatürk Dam Lake (Turkey, Adiyaman) has rich lipid content, a low amount of major minerals and protein content when compared with other economical freshwater species from Turkey. However, the highest levels of the major minerals in Mesopotamian catfish (S. triostegus) were recorded in summer period.