Influence of drying methods on the nutrients, protein content and vitamin profile of basil leaves

Abstract

In this study, basil leaves were dried using natural, microwave-, and convective-drying methods from an initial moisture content of 90.90 +/- 0.1 % to a final one of 8.21 +/- 0.12 %. The natural drying was done in a controlled room at a temperature of 25 +/- 1 degrees C and relative humidity of 60 +/- 5 %. The microwave-drying processes were performed using 100, 300, 500, 700, and 900 W microwave output powers, while 50 degrees C was used in convective-drying. The drying periods of different drying methods lasted between 16.5 and 1620 min. Consequently, the best drying method regarding drying period, energy consumption, protein amount, macronutrients (Cu, Zn, Fe, Mn and B), micronutrients (Cu, Zn, Fe, Mn and B), water-soluble vitamins (ascorbic acid, Vitamin B3 and Vitamin B6), fat-soluble vitamins (beta-carotene, Vitamin E, and Vitamin K), color parameters (L, a, b, C and alpha) and chlorophyll concentration was determined to be microwave-drying at 700 W.