Drying of oat milk pulp enriched with phenolic content by solid-state fermentation using different methods

This study aimed to enrich the bioactive content of oat milk pulp (OMP), a waste product of oat milk production, by fermenting it using Aspergillus oryzae via solid culture fermentation (SCF). Optimum conditions were determined as 50% initial moisture level, 33°C incubation temperature, and 2 days using a Box-Behnken experimental design, and the total phenolic content was 11.55 mg GAE/g DM, which was 1.6 times higher than that of unfermented pulp. Since the moisture content of the fermented pulp produced under optimum conditions was approximately 35%, it was subjected to convection drying at 50, 60, and 70°C to increase shelf life. The highest diffusion coefficient was obtained at 50°C during convection drying. This study aimed to minimize the environmental impact of waste by proposing a process combining fermentation and drying methods to evaluate food industry waste and recycle it into the economy.