Development and quality evaluation of partially lyophilized watermelon (Mateera) juice: Physicochemical and sensory characteristics

Abstract:

Watermelon (Citrullus lanatus) is a nutrient-rich fruit with high moisture content, making it highly susceptible to post-harvest deterioration and limiting its commercial utilization. The present study aimed to develop a functional beverage from indigenous mateera watermelon using partial lyophilization and to evaluate its physicochemical and sensory characteristics. Fresh watermelon juice was extracted, clarified, partially lyophilized, reconstituted and fortified with beetroot powder at different concentrations (0.0-2.5%) to optimize product quality. The physical characteristics of Mateera watermelon were assessed prior to processing to determine its suitability for juice production. Six formulations (T₁-T₆) were subjected to sensory evaluation using a nine-point hedonic scale, and the most acceptable formulation was selected for further quality evaluation. Among the treatments, T₂ (99.5% watermelon juice + 0.5% beetroot powder) recorded the highest overall acceptability and was identified as the optimized formulation. The optimized beverage exhibited desirable physicochemical characteristics, including pH (5.72), total soluble solids (14.00 °Brix), titratable acidity (0.64%), reducing sugars (4.42%), total sugars (4.17 g/100 g), ascorbic acid (5.55 mg/100 g) and lycopene (10.80 mg/kg). The findings demonstrate that partial lyophilization combined with natural beetroot fortification is an effective approach for developing a nutritionally desirable, visually appealing and highly acceptable functional beverage. The developed product offers considerable potential for value addition, reduction of post-harvest losses and commercial utilization of indigenous watermelon resources.