Effects of blenderized watermelon with the rind on satiety, postprandial glucose, and bowel movement, with sensory evaluation

Watermelon is a well-liked fruit containing bioactive compounds and nutrients. Watermelon research on metabolic diseases often involves flesh, yet rind is less explored. This study examined effects of watermelon with rind on satiety, postprandial glucose, and bowel movement with a sensory evaluation in healthy adults. The study included 21 participants (age 23.6 ± 5.7y, BMI 22.6 ± 2.8 kg/m²) in a randomized double-blind crossover design. Participants consumed one cup of blenderized watermelon with and without rind separated by a one-week washout period. Sensory analysis included 23 semi-trained panelists to complete a triangle and a 7-point hedonic scale test. Results revealed significant increase in satiety for both trials over time, with more fullness for watermelon with rind (P < 0.05). Rind stabilized glucose response compared to flesh (P < 0.001). No bowel movement differences were found for either trial. Most sensory panelists (91 %) identified the sample of watermelon with rind in the triangle test (P < 0.001). Higher ratings in color, consistency, smell, flavor, and sweetness for watermelon compared to watermelon with rind (P < 0.01). Overall acceptance was significantly higher for watermelon compared to watermelon with rind (P < 0.001). Findings suggest health-promoting effects of watermelon rind on satiety and glucose, but higher acceptance for watermelon flesh vs watermelon flesh with rind. Future studies should investigate potential benefits of rind in disease prevention and attenuation. Advancement in food technologies is also needed to increase palatability to promote rind consumption.