Effect of Solar and Microwave Assisted Drying on Bioactive Characteristics of Fermented Parkia biglobosa seeds

This study investigated the identification, quantification, and effect of solar and microwave-assisted drying on the bioactive characteristics of fermented Parkia biglobosa seeds. Drying is an important food preservation technique that reduces microbial activity; however, it may alter bioactive compounds, affecting the nutritional value, health benefits, and usability of food products. Therefore, this research aimed to evaluate the impact of different drying methods on bioactive compounds in fermented P. biglobosa seeds and identify compounds associated with potential biological activities. Fermented African locust bean seeds were divided into four groups: fresh (control), microwave-dried at 50°C, microwave-dried at 60°C, and solar-dried samples. Gas chromatography analysis identified 17 major compounds, including Pentadecanoic acid, Linoleic acid, 1,2,3-Benzenetriol, Oleic acid, 13-octadecenal, Tetradecanoic acid, n-Hexadecanoic acid, and other bioactive-related compounds. The results revealed that drying significantly reduced the relative proportions of identified compounds, following the order: fresh > 50°C microwave-dried > 60°C microwave-dried > solar-dried samples. The total proportion of bioactive compounds was highest in fresh fermented seeds (51.79%), followed by microwave drying at 50°C (49.72%), microwave drying at 60°C (41.45%), and solar drying (33.22%). The reduction in bioactive compounds after drying may influence their potential antioxidant, antimicrobial, and anti-inflammatory properties. The study concluded that drying conditions strongly affect the bioactive composition of fermented P. biglobosa seeds, and careful selection of drying temperature and method is necessary to minimize nutrient losses and preserve their functional health benefits.