Peanuts are a nutrient-dense food with considerable potential for further utilisation. However, their nutritional value may be limited by antinutritional compounds, particularly phytic acid and tannins, which can interfere with nutrient absorption. This study investigated the effects of fermentation time on the nutritional composition, antioxidant capacity, and antinutritional content of peanut flour. Fermentation was performed with Rhizopus oligosporus at 1% (w/w). A completely randomised design was applied with three treatments: unfermented peanuts (0 h) and peanuts fermented for 48 and 72 h, with each treatment conducted in triplicate. The findings demonstrated that fermentation significantly improved the nutritional and functional properties of peanut flour. Protein content increased from 25.26% to 30.46%, while total phenolic content rose from 3.61 to 7.38 mg GAE/g. Antioxidant activity also improved, as reflected by the reduction in IC50 value from 184.81 to 96.82 ppm. In contrast, phytic acid content declined from 0.81% to 0.33%, and tannin content decreased from 2.21 to 0.87 mg TAE/g. In conclusion, 72-hour fermentation was identified as the optimal condition for improving both nutritional quality and functional properties. Further studies on bioavailability and industrial application are recommended.
Prayitno et al. (Thu,) studied this question.