Study on the structural characteristics of several marine fish species and gel forming ability of Otolithoides pama of Bangladesh

Abstract

This study evaluated the muscle structural characteristics mainly myotome identification and processing yield of nine marine fish species: Otolithoides pama (Pama croaker), Pennahia pawak (Pawak croaker), Hilsha kelee (Kelee shad), Nemipterus randalli (Randall's threadfin bream), Gazza minuta (Toothed ponyfish), Sillaginopsis panijus (Flathead sillago), Megalaspis cordyla (Torpedo scad), Ablennes hians (Flat needlefish), and Stolephorus indicus (Indian anchovy). The results indicated that O. pama had a muscle yield of 39.35±0.98% of total body weight, comprising 94.84±1.56% white and 5.13±0.97% dark muscle. P. pawak exhibited a muscle yield of 44.59±1.04%, with 98.85±1.62% white and 1.15±0.22% dark muscle. H. kelee had a muscle yield of 40.65±1.05%, consisting of 74.56±0.15% white and 25.45±2.05% dark muscle. N. randalli yielded 44.67±0.18% of its body weight as muscle, with 94.26±0.34% white and 5.73±1.5% dark muscle. S. panijus had a muscle yield of 51.63±1.91%, with 96.34±2.21% white muscle and 3.65±0.91% dark muscle. M. cordyla showed a muscle yield of 40.28±0.93%, with 86.47% white and 13.5±1.45% dark muscle. A. hians had a muscle yield of 48.39± 0.87%, with 97.59±1.85% white and 2.40% dark muscle. S. indicus exhibited the highest yield among the species studied, with a muscle yield of 57.30±0.52%, consisting of 97.52±1.37% white and 2.47±0.21% dark muscle. The gel-forming ability of Otolithoides pama (Pama croaker) was further investigated. To assess the impact of washing and heating on gel formation, a part of the mince was washed with 0.1% NaCl solution. Both washed and unwashed mince were then ground with 3% NaCl for 20 minutes at 4°C. The resulting paste was stuffed into polyethylene tubes and incubated in water baths at 40°C, 50°C, and 60°C for 2 hours (one-step heating), followed by an additional 30 minutes at 90°C (two-step heating) to form gels. The highest gel strength was achieved at 40°C, with the two-step heating process outperforming the one-step heating in terms of gel quality. Washing the mince significantly improved its texture and color, confirming that surimi made from washed mince is superior to that from unwashed mince. The effect of NaCl concentration on gel texture was also explored, with concentrations of 1%, 2%, 3%, 4%, and 5% NaCl. The optimal gel strength was observed at 3% NaCl during grinding. These findings suggest that O. pama is a suitable species for surimi production.