Bioscience Methods 2017, Vol.8, No.2, 18-30
28
Figure 2 Percentage occurrence of fungi isolated from snack samples
3 Discussion
Alkalinity/ acidity of foods affects quality and shelf life because different microbes have different optimum pH,
the pH of snacks treated with the crude extracts and the untreated was analyzed for the effects on microbial
presence and diversity (Table 8). The untreated snack had the least pH (9.60 ±0.1) and highest counts for bacteria
and fungi loads,
Vernonia amygdalina
and
Ocimum gratissimum
crude extracts had effect on the microbial load
but
Ocimum gratissimum
had more effect on both bacteria and fungi load. The mixture of
Vernonia amygdalina
plus
Ocimum gratissimum
reduced bacterial load but had no effect on fungi growth in the freshly produced snack,
from the result of this study, it could be deduced that there may be an antagonizing effect of some phytochemicals
in the plants on freshly produced snacks.
Ocimum gratissimum
had the best effect in reducing bacteria and fungi
loads; and could be a suitable substitute to synthetic preservatives for the preservation of the fish snacks and
probably other processed fish products. Three genera of bacteria,
Bacillus spp, Micrococcus spp and
Staphylococcus
were isolated from both freshly produced and packaged snack
. Micrococcus
species are strictly
aerobic Gram positive cocci bacteria that can contaminate food product through water, dust and handler.
Staphylococcus aureus
as a Gram positive bacterium is a facultative anaerobe which can grow in both aerobic and
anaerobic conditions this probably might be responsible for its being the dominant bacterium, its presence in the
snack could be from atmosphere, water and handlers. The counts of the isolated organisms were still lower than
the limit of 10
3
cfu/g recommended by ICMSF (2002) in Good Manufacturing Practice (GMP). This could be
attributed to the high hygienic standard observed during the processing, and an assurance of the safety of freshly
produced
S. galilaeus
snack consumption.
