Kinetics of Phenolic Compounds Modification during Maize Flour Fermentation
Oluwafemi Ayodeji Adebo,
Ajibola Bamikole Oyedeji,
Janet Adeyinka Adebiyi,
Chiemela Enyinnaya Chinma,
Samson Adeoye Oyeyinka,
Oladipupo Odunayo Olatunde,
Ezekiel Green,
Patrick Berka Njobeh,
Kulsum Kondiah
Affiliations
Oluwafemi Ayodeji Adebo
Department of Biotechnology and Food Technology, Doornfontein Campus, Faculty of Science, University of Johannesburg, Doornfontein, P.O. Box 17011, Johannesburg 2028, South Africa
Ajibola Bamikole Oyedeji
Department of Biotechnology and Food Technology, Doornfontein Campus, Faculty of Science, University of Johannesburg, Doornfontein, P.O. Box 17011, Johannesburg 2028, South Africa
Janet Adeyinka Adebiyi
Department of Biotechnology and Food Technology, Doornfontein Campus, Faculty of Science, University of Johannesburg, Doornfontein, P.O. Box 17011, Johannesburg 2028, South Africa
Chiemela Enyinnaya Chinma
Department of Food Science and Technology, Federal University of Technology, P.M.B 65, Minna 920001, Nigeria
Samson Adeoye Oyeyinka
Department of Biotechnology and Food Technology, Doornfontein Campus, Faculty of Science, University of Johannesburg, Doornfontein, P.O. Box 17011, Johannesburg 2028, South Africa
Oladipupo Odunayo Olatunde
Department of Food and Human Nutritional Sciences, Faculty of Agricultural and Food Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
Ezekiel Green
Department of Biotechnology and Food Technology, Doornfontein Campus, Faculty of Science, University of Johannesburg, Doornfontein, P.O. Box 17011, Johannesburg 2028, South Africa
Patrick Berka Njobeh
Department of Biotechnology and Food Technology, Doornfontein Campus, Faculty of Science, University of Johannesburg, Doornfontein, P.O. Box 17011, Johannesburg 2028, South Africa
Kulsum Kondiah
Department of Biotechnology and Food Technology, Doornfontein Campus, Faculty of Science, University of Johannesburg, Doornfontein, P.O. Box 17011, Johannesburg 2028, South Africa
This study aimed to investigate the kinetics of phenolic compound modification during the fermentation of maize flour at different times. Maize was spontaneously fermented into sourdough at varying times (24, 48, 72, 96, and 120 h) and, at each point, the pH, titratable acidity (TTA), total soluble solids (TSS), phenolic compounds (flavonoids such as apigenin, kaempferol, luteolin, quercetin, and taxifolin) and phenolic acids (caffeic, gallic, ferulic, p-coumaric, sinapic, and vanillic acids) were investigated. Three kinetic models (zero-, first-, and second-order equations) were used to determine the kinetics of phenolic modification during the fermentation. Results obtained showed that fermentation significantly reduced pH, with a corresponding increase in TTA and TSS. All the investigated flavonoids were significantly reduced after fermentation, while phenolic acids gradually increased during fermentation. Among the kinetic models adopted, first-order (R2 = 0.45–0.96) and zero-order (R2 = 0.20–0.82) equations best described the time-dependent modifications of free and bound flavonoids, respectively. On the other hand, first-order (R2 = 0.46–0.69) and second-order (R2 = 0.005–0.28) equations were best suited to explain the degradation of bound and free phenolic acids, respectively. This study shows that the modification of phenolic compounds during fermentation is compound-specific and that their rates of change may be largely dependent on their forms of existence in the fermented products.
