Color Degradation Kinetics of Carrot (Daucus carota L.) Slices during Hot Air Drying

The effect of temperature on color change kinetics of carrot slices was investigated during hot air drying. The color parameters for the color change of the foods were quantified by Hunter L (whiteness/darkness), a (redness/greenness) and b (yellowness/blueness) values. These values were also used for calculation of the total color change (ΔE). The color values (L, a and b) decreased, while ΔE increased during drying. Zero‐ and first‐order kinetic models were applied to describe color change. Mathematical modeling color change kinetics indicated that both models were found to describe the L, a and b values adequately. However, ΔE followed zero‐order kinetics. PRACTICAL APPLICATIONS: In this study, a hot air dryer was used. The effect of air temperatures (45, 55 and 65C) on color change kinetics of carrot slices was investigated. The color of carrot slices was measured during hot air drying. Zero‐ and first‐order kinetic models were applied color change. The first‐order kinetic model adequately described evolution of L, a and b values derived for carrot slices during drying. Dried carrots are used as an ingredient in instant soups or meals and an excellent candidate for developing oil‐free, healthy snack food if the nutritional value can be well preserved.