Effect of added calcium and heat setting on gel forming and functional properties of Sardinella fimbriata surimi.

Present study evaluates the effect of calcium and heat setting on gel characteristics of lesser sardine (Sardinella fimbriata) surimi. Total seven formulations were made namely, S. fimbriata minced meat without heat setting (A1), minced meat with heat setting (A2), S. fimbriata surimi control (without addition of calcium) without heat setting (B1), control (without addition of calcium) with heat setting (B2), surimi added with 0.3% calcium without heat setting (C1) and surimi added with calcium with heat setting (C2) and refiner meat without addition of calcium and with addition of sodium bicarbonate (D). C1 exhibited gel strength of 329 g cm (Grade KA) whereas C2 sample exhibited gel strength of 556.2 g cm (Grade AA) as a result of gel setting at 35 °C for 45 min. Textural parameters such as hardness, chewiness, gumminess and cohesiveness were improved in C2 when compared with all other formulations. Addition of calcium and sodium bicarbonate significantly improved whiteness of surimi with gel setting in comparison to other treatments (p < 0.05). C2 samples exhibited reduced thio barbituric acid (TBA) values indicating lower oxidation. Results indicated potential for use of fish species with high fat content and darker meat for surimi manufacture with gel setting of sol and addition of sodium bicarbonate and calcium as ingredients.

Characterization of chitin extracted from enzymatically deproteinized Acetes shell residue with varying degree of hydrolysis.

Acetes shrimp is an unexploited tiny shrimp mainly landed as bycatch which is a good source for the recovery of protein and chitin. In the present study, the residual shell obtained after the hydrolysis of Acetes was used for the extraction of chitin by combining enzymatic and chemical treatments. Enzymatic hydrolysis with Alcalase was performed at different rates. Results showed that the protein removal efficiency increases with the increase in DH and the maximum deproteinzation was achieved at 30 % DH (93.68 %). The FTIR spectra showed two sharp bands for chemically prepared chitin and 30 % DH chitin at 1627-1629 and 1664-1665 cm-1 indicating that its alpha amorphous structure. The degree of N-acetylation was found to be higher in enzymatically prepared chitin in all different hydrolytic treatment rather than chemically prepared. The surface morphologies of chitin revealed the porous and nanofibrous structures for 30 % DH chitin and chemically prepared chitin.