Optimization and evaluation of carrot flour production using refractance window drying technology: a study on nutritional and sensory properties.

Abstract

Carrots (Daucuscarota L.) are recognized for their high nutritional value, particularly their rich β-carotene content, but their high moisture content makes them highly perishable. Drying is a commonly used preservation method to address this challenge, helping to extend shelf life and stabilize the product. Refractance Window Drying (RWD) is a relatively new technology that offers the advantage of preserving both nutrients and sensory qualities. This study focused on optimizing the drying conditions for carrot flour production using RWD and evaluating its nutritional, drying, and sensory properties.The study used Design-Expert®12 software to test combinations of drying temperatures (80–95oC) and durations (60–90 minutes). Key quality parameters assessed included moisture content, vitamin C, and β- carotene levels. From 22 experimental runs, the optimal drying conditions were determined to be 89.7oC for 83 minutes. Under these conditions, the carrot flour retained 8.7% moisture, 25.1 mg/100 g vitamin C, and 69.9 μg/g β-carotene. The flour’s composition included 10.83% moisture, 6.60% ash, 2.53% fat, 34.83% dietary fiber, 7.00% protein, and 38.01% carbohydrates. When the flour was incorporated into cookies, sensory evaluation scores ranged from 5.3 (neutral) to 7.9 (moderately liked), with the control sample scoring the highest.This study highlights the potential of RWD as a reliable method for producing highquality carrot flour, which retains its nutritional benefits and can be effectively used in baked products. The findings offer practical insights for reducing carrot post-harvest losses and promoting their use in value-added food applications.