Biochemical and Bacteriological Quality of Rohu (Labeo rohita) Head Sauce Produced by Enzymatic and Fermentation Method

A sauce was produced by enzymatic and fermentative
methods using the heads of freshwater fish rohu
(Labeo rohita) with solar salt concentration of 25% (wI
w). Commercial papain (3%, wjw) was used for
enzymatic hydrolysis and stored at room temperature
for 120 d. Pediococcus pentosaceus FSBP 4-40
(10%, v/w) with the cell concentration of aproximately
8 log cfu ml-1 and dextrose (7.5%, w/w) was used
for fermentative production at 37"C for 120 d.
Changes in yield, water activity (aw )' total valatile
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 enzymatically and fermentativley
produced rohu head sauce was observed. Bacteriological
parameters such as total plate count,
Escherichia coli, lactic acid bacteria, staphylococci,
total halophile count and yeast and mold counts
were determined at different time intervels The
result suggested that TSN, NPN, TA and DH
significantly increased (p<O.05) in treated samples
compared to control. However, aw' pH, moishtre, fat,
TYB-N, fatty acid concentration and L*, a*, b* values
showed changes. The antioxidant properties like
total antioxidant activity, 2,2'-diphenyl-lpicrylhydrazyl
(DPPH), super oxide anion
scavanging activity and reducing potential of the
lyophilized rohu head sauce samples were found to
be sigificandy higher (p<0.05) in enzyme/bacteria
treated samples than control. Bacterial counts after
.E-mail: bl!flskar@cjlri.res.in sguom@ynhoo.com
120 days were significantly lower (p<0.05) in the
fennentatively produced rohu head sauce than
enzymatically prepared sauce.