Enzyme activity and constituent extractability of kilned and non-kilned oats at pH values relevant for acidic food fermentations
2025
Ewoud Blontrock | Eline Lambrechts | Frederik Janssen | Yamina De Bondt | Sarah Vanhove | Jolien Lemoine | Christophe M. Courtin | Arno G.B. Wouters
Oat fermentation is often hampered by reduced enzymatic activity caused by kilning. We here investigate whether different enzymatic activities of oats at acidic-fermentation-relevant pH can enhance their nutritional and functional properties. Enzymatic activity (protease, xylanase, β-glucanase, amylase, phytase, and lipase) was assessed in kilned and non-kilned oat suspensions at pH 3.5–7.0. Then, changes in dietary fibre and protein extractability and starch and phytate hydrolysis were evaluated after a 24-h incubation (with added antimicrobials to ensure no fermentation occurred) at pH 6.4, pH 4.0, and under gradual acidification. Non-kilned oats exhibited higher enzymatic activities overall. Arabinoxylan and β-glucan extractability of non-kilned oats (23–26 % and up to 73 %, respectively) were higher than of kilned oats (11–12 % and 40–46 %, respectively). Incubated non-kilned oat demonstrated higher starch (4–5 %) and phytate hydrolysis (43–49 %). These findings highlight the potential of fermenting non-kilned oats to improve oat-based foods like sourdough bread and fermented dairy or meat alternatives.
显示更多 [+] 显示较少 [-]