Evaluation of Enzymatic Hydrolysis of Big Head Fish (Hypophthalmich thysnobilis) Viscera and Use of Obtained Hydrolysates as a Source of Peptones for Growth of Lactobacillus plantarum

With relatively high level of global fish catch, and following it, by the processing industries which have produced high volumes of by-products, very little effort has been done to produce hydrolyzed protein from this material, and to be discarded without any Environmental justification. If these biological compounds be used correctly, on the one hand caused reduce the environmental pollution due disposing of it and the other hand due to high protein value, are recyclable. In this study, first the effect of three different enzymes including papain, pepsin, trypsin(with a concentration of1.5 % of protein substrate) and its influence times (30, 60 and90 min) was investigated on hydrolysis rate of the big head fish viscera to protein recovery. Therefore, the recovered protein was used as a source of peptones to promote the growth of Lactobacillus plantarum and optical density was measured after0, 3, 6, 9, 12, 15, and18 hours incubation. Results showed that the papain enzyme in duration time of 90 minutes had the highest yield of hydrolysis degree and protein production. It also observed that the growth of Lactobacillus plantarum has been more in medium containing of peptone derived from enzymatic hydrolysis compared with commercial MRS medium as the control sample. The results showed that there is a good potential for producing hydrolyzed protein with high nutritional value from fish by-products.