Enzymatic and Fermentatively Produced Rohu (Labeo rohita) Sauce and its Biochemical and Microbiological Quality

摘要

Rohu (Labeo rohita) sauce was produced by enzymatic and fermentative method using optimized conditions carried out through response surface method. Solar salt (20%, w/w) and commercial papain (3%, w/w) were used in the sauce produced by enzymatic method. The optimized conditions for fermentative production of sauce were 25% salt (w/ w), 7.5% sugar (w/w) and 10% (w/v) inoculum (Pediococcus pentosaceus FSBP4-40) with the cell concentration of approximately 8 log cfu ml'1. The sauces produced by enzymatic and fermentative method were stored at room temperature and 37°C, respectively for 180 days. Changes in yield, water activity (aw), total volatile base nitrogen (TVB-N), total soluble nitrogen (TSN), non protein nitrogen (NPN), titratable acidity (TA), degree of hydrolysis (DH) and fatty acid composition of both the sauce samples were observed. The result suggested that TSN, NPN, TA and DH significantly increased (p<0.05) in treated samples compared to control (sample without added papain and P. pentosaceus FSBP4-40). However, aw, pH, moisture, fat, TVB-N, fatty acid concentration and L*, a*, b* values showed different changes. Sensory properties of enzyme treated sauce had slightly higher score than the lactic acid bacteria fermented sauce. Bacterial counts after 180 d were significantly lower (p<0.05) in the fermentatively produced rohu sauce than enzymatically prepared sauce. The study emphasizes the importance of optimized use of enzyme and native lactic acid bacteria for the acceleration of fermentation process to produce biofunctionally and bacte-riologically superior rohu sauce.