Evaluation of Lycopene Loss and Colour Values in Convective Drying of Tomato by Surface Response Methodology

Abstract

Abstract The increasing interest in the antioxidant activity of lycopene has been to promote the consumption of tomato and tomato-based products. The aim of this work was to evaluate tomato (Lycopersicon esculentum Mill) drying in thin layer through response surface methodology. The independent variables investigated in this study were drying air temperature (60, 70 and 80°C) and wet sample thickness (3, 5 and 7 mm). The drying condition with the lower colour value (Hue angle) and higher lycopene content was 60°C and sample thickness of 3 mm. In this condition, the responses for the colour (Hue angle) and lycopene content values were 47.7 0.2° and 301.9 3.1 μg g– 1, respectively. The lycopene loss was similar to that reported in the literature (30–50%) using more expensive methods of tomato drying such as freeze-drying and lyophilization.