Abstract:
In the current study, probiotic yeast strain, Saccharomyces cerevisiae
AKP1 was assessed for its potential as a starter culture in
multi-grain (rice, pulses, and soybean, 3:1:1) substrates fermentation.
The impact of fermentation of multi-grain-based food on
proximate composition, antinutrients, and antioxidants was
evaluated. Fermented product showed significant increments
(P <.05) in protein (13.6%) and fiber (1.8%) content. Moreover,
the rapidly digestible starch (27.5%) and resistant starch (15.0%)
levels were found to increase significantly (P <.05) while the
slowly digestible starch level decreased (87.7%) in the fermented
food sample. After 4 days of fermentation, total phenolic
and total flavonoid contents increased by 83.0% and 69.8%,
respectively, with a greater antioxidant potential of 85.9%. The
fermented food sample showed a significant reduction in the
phytate (64.5%) and trypsin inhibitor activity (19.9%) (P <.05)
with a substantial increase in phytase level (P <.05). Fourier
transform infrared spectroscopy clearly revealed the alteration
of physico-chemical properties during fermentation with
S. cerevisiae AKP1. Gas chromatography–mass spectrometry
analysis detected the presence of 38 volatile compounds in
the fermented food material with the prevalence of fatty acids
such as palmitic acid, linoleic acid, among others; alcohols such
as isoamyl alcohol, 2,3-butanediol, among others; and esters
such as ethyl-2-methylbutanoate. Thus, probiotic yeast
S. cerevisiae AKP1 could improve the dietary and functional
characteristics of multi-grain substrates and could be regarded
as a potential starter for multi-grain substrates fermentation.