Effect of freeze drying and batch type window refractance drying on the quality characteristics of mango leather

Abstract

Mango leather is a nutrient-rich, shelf-stable snack made by pureeing and drying mango pulp into thin, flexible sheets. It plays a key role in reducing postharvest losses and adding value to surplus mango production. This study investigated the effect of freeze drying and batch-type window refractance drying (BTWRD) on the quality characteristics of mango leather. Drying methods significantly (p < 0.05) affected all quality parameters. Key nutritional components varied within the following ranges: moisture (5.70–7.61%), protein (1.32–1.57%), fat (0.62–1.76%), fiber (3.72–4.86%), ash (1.64–2.17%), and carbohydrates (82.02–86.99%). Bioactive compound retention also differed, with total carotenoids (522.87–543.82 µg/g), phenolics (0.62–0.97 mg GAE/g), flavonoids (1.25–1.97 mg QE/g), and vitamin C (65.64–127.34 mg/100 g) showing significant variation between treatments. Color attributes (L*, a*, b*, chroma), pH, titratable acidity, total soluble solids, and water activity were likewise affected. The findings of this study indicate that freeze drying produced mango leather with superior quality across most attributes, while BTWRD emerged as a viable alternative, offering considerably shorter drying times (2.33 h) with good quality retention.