Optimization of microwave-assisted drying methods for optimizing quality, nutrient retention, and color stability of sweet cherries

OpenAlex İngilizce

The aim of this study was to optimise drying methods for sweet cherries (Prunus avium) in order to extend their shelf life while preserving their nutritional and bioactive compounds. Cherries are highly perishable due to their high moisture content, requiring effective drying techniques. Three methods were evaluated: microwave drying (MWD), microwave-assisted hot air drying (MWHAD) and solar tunnel drying (STD). Key parameters included drying time, drying rate, colour stability, and the retention of sugars, organic acids, and phenolic compounds. MWD was tested at 180, 360 and 540 W; meanwhile, MWHAD involved combining microwave treatment with hot air at temperatures of 100, 180 and 230 °C. Drying time decreased with increasing microwave power; MWHAD reduced drying time by ∼25 % compared to MWD. Although STD was cost-effective, it took 126 h, reduced to 82 h with solution pre-treatment. Colour stability was best preserved in the MWHAD process at 180 W and 160 °C without a solution, closely resembling fresh cherries. The highest sugar content (glucose: 259.37 mg/100 g; fructose: 229.68 mg/100 g) was achieved at 180 W and 160 °C with a solution. Meanwhile, organic acids (malic acid: 28,431.56 mg/kg) were best retained at 540 W without pretreatment. Phenolic compounds were maximally preserved under MWHAD at low power (180 W) and a moderate temperature (up to 160 °C) when using a solution. Overall, MWHAD under optimised conditions effectively balanced drying efficiency with the retention of biochemical integrity, colour and nutritional quality. These findings support MWHAD as a scalable, efficient approach for producing high-quality dried cherries. • Optimised cherry drying methods extend shelf-life while preserving bioactive compounds. • MWHAD efficiently preserves color and bioactive compounds in dried cherries. • Microwave power and hot air temperature in MWHAD strongly affect drying efficiency. • Solution pre-treatment enhances sugar and phenolic compound retention. • Optimised MWHAD offers scalable, high-quality dried cherries for industrial application.