Stabilization and Storage Kinetics of Oat Bran Treated by Microwave, Convection Heating, and Freeze‐Drying‐Assisted Thermal Processes

ABSTRACT Background and Objectives Oat bran is highly susceptible to hydrolytic and oxidative deterioration due to its high lipase activity and lipid content, limiting its storage stability and utilization as a value‐added food ingredient. This study investigated microwave (MW), industrial convection oven (OVEN), freeze‐drying‐assisted microwave (FD + MW), and freeze‐drying‐assisted oven (FD + OVEN) treatments on oat bran quality over 90 days at room temperature using experimental analyses and kinetic modeling. Findings All treatments significantly reduced lipase activity and delayed hydrolytic and oxidative deterioration compared with the untreated control. FD‐assisted treatments showed the best performance, reducing lipase activity to 3.32 and 2.78 U/g and decreasing initial free fatty acidity (FFA) and peroxide value (PV) while preserving the highest antioxidant capacity. Total phenolic content (TPC) increased from 44.08 to over 62 mg GAE/100 g following FD‐assisted stabilization. FFA, lipase activity (LA), PV, and DPPH followed first‐order kinetic models, whereas TPC followed zero‐ or first‐order kinetics depending on treatment. Thiobarbituric acid value (TBA) formation fitted a sequential first‐order reaction model, while ABTS • + showed no regular pattern for reliable kinetic modeling. Conclusions FD‐assisted treatments showed the greatest improvements in oat bran oxidative stability and bioactive quality retention during storage. Significance and Novelty Combining stabilization performance with kinetic modeling provides a quantitative basis for shelf‐life prediction and supports oat bran valorization as a functional food ingredient.