Single Cell Protein Production From Kilka Stick Water by Lactic Acid Bacteria

One of the most important problems in kilka meal factories is stick water production, as a waste, from meal production process. Five hundred litters of stick water is produced for each 1000 kg of kilka fish. This waste has rather high protein and might be used as substrate for the growth of bacteria such as lactic acid bacteria. In this study Lactobacillus bulgaricus and Lactobacillus plantarum were used for SCP production from stick water. Adaptation of Lactic AcidA bacteria to pure stick water was performed by increasing the concentration of stick water in distilled water. The growth of bacteria was studied by spectrophotometric method and reading the optical density of bacteria at 600 nm. The effect of glucose, as additional substrate on SCP production, was also evaluated. After separation of biomass, the final product was lyophilized by freeze dryer and then was analyzed for amino acid profiles, total protein, total fat, moisture and ash.The results showed that the amount of produced SCP from L. plantarum and L. bulgaricus were 13-15 g/l and 16-19 g/l in normal stick water and 20-22 g/l and 21-25 g/l in the presence of glucose respectively. Mean value of total protein, total fat, moisture and ash in produced SCP were 82.26%, 1.02%, 0.54% and 15.58% whereas the percent of these values in stick water were 5.15%, 2.26%, 92% and 0.57% respectively. The results showed that amino acids composition in produced SCP is comparable with the suggested pattern of requirement by FAO/WHO.