Effect of Natural and Forced Convective Drying on the Nutritional and Physicochemical Quality of Tomatillo (Physalis ixocarpa): A Multivariate Analysis Approach

This study evaluated the effects of four drying treatments, namely natural (shade) drying and convective hot-air drying at 50, 65, and 80°C, on the physicochemical properties, mineral composition, and vitamin content of tomatillo ( Physalis ixocarpa L.). Significant changes in color parameters and nutrient degradation were observed, with natural drying causing the greatest losses. Protein and macro-mineral contents decreased under all drying treatments, with the most pronounced reductions occurring in naturally dried samples. Iron and zinc showed notable reductions among micro-minerals, while sodium was better retained at higher temperatures. Water-soluble vitamins, including ascorbic acid, thiamine, riboflavin, niacin, pantothenic acid, and pyridoxine, experienced substantial losses, particularly in natural drying, while moderate-temperature drying (65°C) retained more. Fat-soluble vitamins, including beta-carotene, zeaxanthin, lutein, phylloquinone, and alpha-tocopherol, were also affected, though retention was better at 65°C. Multivariate analysis revealed strong positive correlations between total ascorbic acid and zinc (r=0.99), beta-carotene and alpha-tocopherol (r=0.92), and zeaxanthin and lutein (r=0.92), indicating potential synergistic antioxidant effects. • Natural drying caused the greatest losses in tomatillo nutrients • Convective drying at 65°C gave the best overall nutrient retention • Color parameters were significantly altered by drying method and temperature • Protein, minerals, and vitamins were all significantly affected by drying • Multivariate analysis revealed strong correlations among key nutrients