Genomics and Applied Biology, 2017, Vol.8, No.3, 17-25
20
Table 4 Total titratable acidity obtained during fermentation of milled cassava peels
Fermenting Organism
Total titratable acidity obtained during fermentation (%) / period of fermentation (hours)
0
24
48
72
96
Control
0.58 ±0.04
b
0.66 ±0.06
a
1.30 ±0.04
c
1.94 ±0.07
d
2.220 ±0.56
d
Lactobacillus
sp
0.52 ±0.04
b
0.66 ±0.00
a
1.30 ±0.04
c
2.22 ±0.04
e
2.23 ±0.04
d
C. manihot
.
0.42 ±0.00
a
0.82 ±0.04
b
0.90 ±0.00
a
1.16 ±0.04
a
1.22 ±0.04
a
S. exguus
0.42 ±0.00
a
0.88 ±0.04
b
0.82 ±0.04
a
1.54 ±0.04
b
1.54 ±0.04
b
Geotrichum candidum
0.68 ±0.04
c
0.58 ±0.04
a
1.10 ±0 .04
b
1.78 ±0.04
c
1.84 ±0.07
c
Mixed microbes
0.58 ±0.05
b
0.58 ±0.04
b
1.22 ±0.04
c
1.96 ±0.04
d
1.84 ±0.07
c
Note: Each value is Means ±Standard deviation of three replicates. Values followed by the same letter in the same column are not
significantly different using Tukey’s Test at * (P < 0.05)
1.6 pH of fermented milled cassava peels
The result of the pH of the fermented cassava on Table 5 reveals that the pH of the fermented cassava peels
decreases as period of fermentation increases in all the treatments and control experiment. The control experiment
had a pH of 8.90 which was the highest observed at the beginning of fermentation while the least pH at the same
instant of time was recorded in the cassava peels treated with by
S .exguus
. At 96 h of fermentation, the pH value
C. manihot
,
S. exguus
and mixed microbes’ treatments showed no significant difference at P < 0.05. Nevertheless,
the highest pH of 5.97 was recorded in the mixed microbes’ treatment while the lowest pH of 5.40 was recorded in
G. candidum
’s treatment.
Table 5 Daily pH of fermented of milled cassava peels
Fermenting Organism
pH of fermented cassava peels and period of fermentation (hours) for wet sample
0
24
48
72
96
Control
8.90 ±0.00
d
7.93 ±0.06
c
7.37 ±0.06
d
6.07 ±0.06
bc
5.70 ±0.1
bc
Lactobacillus
sp
8.23 ±0.06
c
7.97 ±0.06
c
6.20 ±0.00
a
5.87 ±0.05
a
5.57 ±0.06
ab
C. manihot
.
8.03 ±0.06
ab
7.53 ±0.06
b
6.87 ±0.06
c
6.40 ±0.00
d
5.90 ±0.10
cd
S. exguus
7.97 ±0.06
a
7.53 ±0.06
b
6.97 ±0.06
c
6.20 ±0.00
c
5.87 ±0.06
cd
Geotrichum candidum
8.13 ±0.58
bc
7.30 ±0.06
a
6.83 ±0.06
c
6.03 ±0.06
bc
5.40 ±0.00
a
Mixed microbes
8.17 ±0.58
bc
7.67 ±0.06
b
6.53 ±0.06
b
6.00 ±0.00
ab
5.97 ±0.12
d
Note: Each value is Means ±Standard deviation of three replicates. Values followed by the same letter in the same column are not
significantly different using Tukey’s Test at * (P < 0.05)
1.7 Proximate analysis of the milled cassava peels before and after fermentation
The result of the proximate analysis of the cassava peels before and after fermentation is shown on Table 6. The
percentage carbohydrate in all the treatments including the control experiment decreased after 96 hours of
fermentation. The lowest percentage of carbohydrate of 48.13% was recorded in
L.
plantarum
’s treatment while
the highest percentage of carbohydrate (54.48%) after treatment was observed in
G.candidum
’s treatment. The
percentage protein in all the treatments increased but the highest percentage protein content after 96 hours of
fermentation (26.83 ±0.01) was recorded in
L. plantarum
’s treatment while the lowest percentage of carbohydrate
(23.31) was recorded in
G. candidum
’s treatment.
All the fermenting organisms (treatments) used for the fermentation of the milled cassava peels caused increase in
the protein content of the peels after 96 hours of fermentation, and the percentage values of protein after 96 hours
of fermentation, were significantly different from the initial percentage protein content of the wet cassava peels
before fermentation. However, significant differences were also shown among treatments in their percentage
protein after 96 hours of fermentation. The highest and lowest percentages of protein after 96 hours of
fermentation (26.86 and 23.31%) were recorded in the
L. plantarum
and
G. candidum
treatment respectively.
