Effect of Thermal and Non-Thermal Treatments on the Bioaccessibility of Vitamin C and Carotenoids in a Mixed Tropical Fruit Beverage

A mixed functional beverage was developed using mango, pineapple, and acerola pulps combined with Brazil nut extract, targeting the nutritional and physiological needs of the elderly. The formulation was designed to deliver vitamin C and carotenoids, while maintaining viscosity compatible with level 3 of the IDDSI scale, ensuring safe consumption for individuals with dysphagia. The product underwent different processing treatments, including thermal pasteurization, sterilization, and non-thermal ultrasound processing, to evaluate their effects on bioactive compounds and in vitro bioaccessibility. Vitamin C content and total phenolic compounds decreased by 15.4% and 12.7% after pasteurization, respectively, and by 41.6% and 79.1% after ultrasound treatment. In contrast, sterilization did not result in a significant difference in vitamin C content compared with the control. Conversely, total carotenoid content increased significantly across all processing treatments, while antioxidant capacity remained stable across the different processing conditions evaluated. In addition, a 95% increase in selenium content was observed after pasteurization, indicating enhanced solubilization of mineral fractions in the Brazil nut extract. Vitamin C bioaccessibility reached 53.24% after ultrasound treatment and 38.58% after sterilization, outperforming the control (34.59%). For carotenoids, sterilization resulted in the highest bioaccessibility (28.33%), followed by ultrasound (17.21%) and pasteurization (15.24%). The beverage also showed good sensory acceptance among elderly consumers, demonstrating that the formulation successfully combines nutritional adequacy and acceptance. These findings support its potential as a functional beverage that promotes safe nutrition and hydration in older adults, including those with dysphagia.