STUDY ON STRUCTURAL CHARACTERISTICS AND COMPOSITION OF TWO MARINE FISH SPECIES (Dussumieria acuta, Sardinella fimbriata) OF BANGLADESh

Abstract

Two marine fish species, Dussumieria acuta and Sardinella fimbriata were subjected to determine overall muscle structure, processing yields, nutritional composition and variation of nutritional composition with muscle type (dark, white and mixed), location (head, middle and tail) and with different cooking methods (boiling and frying). Gel forming ability of the fish muscle and comparison of their gel-forming with washed and unwashed muscle have been studied at various temperature . Dussumieria acuta had 3.86% dark and 96.2% white muscle, while Sardinella fimbriata had 7.87% dark and 92.32% white muscle. Analysis of nutritional composition of dark, white and mixed muscle showed that, white muscle possess higher moisture (72.12±1.17%, 73.29±0.91% in Dussumieria acuta and Sardinella fimbriata) and crude protein (24.75 ± 1.09% in Dussumieria acuta and 25.09 ±0.90% in Sardinella fimbriata) and dark muscle possess higher lipid content (2.21±0.17% and 2.23±0.44% both in Dussumieria acuta and Sardinella fimbriata). Comparison of nutritional composition of muscles from different parts of fish body showed that moisture percentage was significant in head muscle (73.56±1.87% and 73.58±1.08% in Dussumieria acuta and Sardinella fimbriata). Tail region had significant lipid content of 2.46 ±0.03% and 2.35±0.06% in Dussumieria acuta and Sardinella fimbriata, respectievly. In both fish moisture showed a declination with boiling and frying. Highest moisture loss was found in case of frying which is 56.46± 1.09% in Dussumiera acuta and 55.21±1.02% in Sardinella fimbriata. Highest crude protein percentage was found from boiled samples in both dry and wet weight basis (3.73±0 .18% and 3.30±0.35 % in Dussumieria acuta and Sardinella fimbriata respectively). Fried samples got highest lipid percentage, in frying which is 12.54±1.62% in Dussumiera acuta and 13.07±0.61% in Sardinella fimbriata. Significant ash content was found in fried sample (3.73±0.18% and 3.30±0.35 % in Dussumieria acuta and Sardinella fimbriata, respectively). The gel forming ability and the strength of both Dussumiera acuta and Sardinella fimbriata were investigated under different temperature conditions (40, 50 and 600 C) in water bath for a 120 minute. Highest breaking force was found at 500 C in both washed and unwashed fish muscle paste in both fish mince. Washing of mince results in better quality gels