Abstract
Garcinia lanceifolia Roxb. (Rupohi thekera), an underutilized minor fruit from Assam, holds significant potential as it exhibits substantial traditional medicinal properties. However, its preservation and utilization remain limited, necessitating effective processing techniques. This study aimed to compare the impact of tray drying and freeze drying on the physico-chemical, antioxidant, and functional properties of G. lanceifolia. Fresh fruits were processed using both methods, followed by detailed analyses of nutritional composition, phytochemical content, antioxidant activity, and functional properties. Freeze drying resulted in greater retention of moisture (12.42 ± 0.81%), protein (4.44 ± 0.19%), carbohydrate content (8.29 ± 0.31 g/100 g), and reducing sugar (1.95 ± 0.12%), along with prominent color quality, while no significant difference in ash content was found for either drying method employed. Phytochemical extraction using different solvents (water, n-hexane, 80% methanol, 80% ethanol, and 80% acetone) revealed that freeze-dried samples extracted with acetone had the highest total phenolic content (634.00 ± 1.73 mg GAE/100 g), while methanol extraction yielded the highest total flavonoid content (382.33 ± 1.52 mg QE/100 g). Tray drying, on the other hand, exhibited superior DPPH and FRAP when subjected to ethanol extract (80.24 ± 0.42% and 83.83 ± 0.46 mg/100 g, respectively) and metal chelation capacity (23.69 ± 2.09%). Additionally, functional properties, such as glucose adsorption capacity and α-amylase inhibition, were found to vary between drying techniques, with freeze-dried samples showing better glucose adsorption and tray-dried samples demonstrating greater α-amylase inhibition. FTIR analysis highlighted distinct structural attributes of bioactive compounds retained through both methods. The findings underscore the potential of freeze drying for nutrient preservation and tray drying for cost-effective applications, paving the way for the industrial valorization of G. lanceifolia as a functional food ingredient.