This study was initiated to identify the dominant microbial species and investigate their
activities during the fermentation of soybeans to daw adaw a.
The dominant microorganism s present in both the boiled and roasted soydaw adaw a,
which were spontaneously fermented for 72 h, were isolated, characterized and
identified using an API kit. The proteinase and a -a m y lase activities o f the
microorganism s were determined. Q quality indices such as pH, m oisture, protein and fat
contents of the soydaw draw a were measured. The breakdown of proteins during
ferm entation o f soydaw adaw a w as studied using Gel electrophoresis. The trend in the
level o f sugars during ferm entation o f soydaw adaw a w as carried out using the Lane and
E ynon’s method. A rom atic com pounds (GC-M S m ethod) produced by the different
types o f soydaw adaw a w ere also determ ined.
Results show ed that Bacillus species w ere the dom inant m icro-organism s found and
w hich increased from 10'’ to 10n cfu/g and 103 to 109 for the boiled and roasted
soydaw adaw a from the start to the end o f ferm entation respectively. Lactic acid
bacteria ( 104 to 106 cfu/g) w ere also found. Bacillus supplies accounted for 48% o f the
representative isolates taken from various stages o f fermentation. Other Bacillus
species accounted for 8% to 16% o f the isolates. All the identified Bacillus species
demonstrated proteolytic activity in the order Bacillus subtilis >Baciflus furmis >
Bacillus cerm s > Bacillus pumilus. At a = 0.05, proteolytic activity w as significantly
affected by fermentation time and production method. H ow ever, there was no
interaction betw een these tw o factors.
a-am y lase activity w as positively affected by ferm entation tim e, increasing with
increase in ferm entation time.
H ydrolysis o f proteins during ferm entation w as confirm ed in^soydaw adaw a bv an
increase in the fraction o f low er m olecular weight proteins and m ore distinct bands.
The level o f sugars increased in the first 24 hours but decreased subsequently as
ferm entation progressed.
A rom a com pounds produced w ere m ore in the roasted products than the boiled. Both
products w ere dom inated by 3-H exanol and 9, 12-O ctadecanoic acid. H ow ever,
Tetradecanoic acid and 1,2-Benzene dicarboxylic acid w ere found only in the roasted
Edu, F (2021). The Microbial Activities Involved In The Alkaline Fermentation Of Soybeans Into Dawadawa. Afribary.com: Retrieved May 12, 2021, from https://afribary.com/works/the-microbial-activities-involved-in-the-alkaline-fermentation-of-soybeans-into-dawadawa-1
Frontiers, Edu. "The Microbial Activities Involved In The Alkaline Fermentation Of Soybeans Into Dawadawa" Afribary.com. Afribary.com, 26 Apr. 2021, https://afribary.com/works/the-microbial-activities-involved-in-the-alkaline-fermentation-of-soybeans-into-dawadawa-1 . Accessed 12 May. 2021.
Frontiers, Edu. "The Microbial Activities Involved In The Alkaline Fermentation Of Soybeans Into Dawadawa". Afribary.com, Afribary.com, 26 Apr. 2021. Web. 12 May. 2021. < https://afribary.com/works/the-microbial-activities-involved-in-the-alkaline-fermentation-of-soybeans-into-dawadawa-1 >.
Frontiers, Edu. "The Microbial Activities Involved In The Alkaline Fermentation Of Soybeans Into Dawadawa" Afribary.com (2021). Accessed May 12, 2021. https://afribary.com/works/the-microbial-activities-involved-in-the-alkaline-fermentation-of-soybeans-into-dawadawa-1