During fermentation, the pH of the liquor samples first
showed a decreasing trend up to the eighth day and
thereafter started rising (Fig. 1). An initial decrease in
pH was noticed in samples and that could be due to
the ability of the strain B. subtilis to initially use sugar
as substrates for their growth19 and simultaneously they
produce acid via pyruvate.20 Low pH condition prevents
the decay of shrimp shell, which are colonized by spoilage
and pathogenic organisms.21 By the eighth day,
about 87% of the sugar in the jaggery broth was utilized
by the organism. Therefore, when the sugar substrate
was depleted, acid production decreased and pH started
increasing.22 The acid produced was responsible for the
extent of demineralization noticed in the samples at the
end of fermentation.12 During fermentation, proteolysis
occurs and ammonia is released due to utilization of
amino acids for the growth of the bacteria.19,23–26 This
also might have caused the increase in pH.