Vitamin losses during frozen storage of L iza aurata ( R isso, 1810) , C yprinus carpio L . 1758 , C lupeonella cultriventris caspia ( N ordmann, 1840) , R utilus frisii kutum ( K amenskii, 1901) and S ander lucioperca ( L ., 1758)

Summary The objective of this study was to determine the fat and water‐soluble vitamins contents ( A , E , D , K , B 1 , B 2 , B 6 , B 12 , niacin, biotin, ascorbic, folic and pantethonic acids; in mg kg −1 fresh weight) lost during frozen storage (−24°C) in time intervals of 0, 1, 2, 3 and 4 months. Studied species included: L iza aurata (golden grey mullet), C yprinus carpio (common carp), C lupeonella cultriventris caspia (common kilka or sprat), R utilus frisii kutum ( C aspian kutum) and S ander lucioperca (pike perch). Results showed that A , D and K vitamin losses occurred in all samples during storage, but no statistically significant differences were observed. Vitamin E losses under frozen conditions were significant in common kilka, Caspian kutum and pike perch, however, not in golden grey mullet or common carp. A decrease in vitamin C was significant in all fish species, but there were no significant decreases in other water‐soluble vitamins ( B 1 , B 2 , B 6 , B 12 , niacin, folic acid, pantothenic acid, biotin).