Title : Prebiotic pumpkin in syrup as a functional food option to support metabolic health in people with overweight, obesity and diabetes
Abstract:
The rapid increase in overweight, obesity and type 2 diabetes has intensified the demand for sweet food options that provide sensory pleasure while exerting a lower glycaemic impact and offering additional physiological benefits. In this context, candied fruits reformulated with prebiotic ingredients and reduced-calorie sweeteners represent a promising strategy for developing functional foods adapted to metabolic disorders. The present work describes the design of a prebiotic pumpkin in syrup obtained from Cucurbita moschata cubes processed through a combined sequence of prefreezing, calcium treatment and osmotic dehydration in a binary sucrose–xylitol solution. This approach aims to preserve structure and texture, reduce the overall energy density and incorporate a sugar alcohol with documented prebiotic potential and low glycaemic index, thereby aligning the product with the nutritional needs of individuals with overweight, obesity and diabetes. Fresh pumpkin was selected at commercial maturity, standardised in size and characterised for initial moisture to allow accurate description of mass transfer during processing. Half of the cubes were subjected to prefreezing at sub-zero temperatures followed by controlled thawing to induce microstructural modifications that enhance water removal and solute uptake during the osmotic step. A subsequent immersion in calcium hydroxide solution promoted calcium pectate formation within cell walls, increasing tissue firmness and resistance to thermal damage. Osmotic dehydration was then carried out in a 65° Brix sucrose–xylitol solution (1:1, w/w) at different temperatures and contact times under constant agitation. Water loss, solid gain, changes in soluble solids and colour were evaluated to characterise process performance and product quality. The combined prefreezing and calcium pretreatment improved structural stability, enabling high solid incorporation without disintegration of the pumpkin matrix. The inclusion of xylitol reduced the caloric content relative to conventional sucrose-based candied products and introduced a prebiotic component. The process conditions that delivered optimal water removal and solid gain were associated with strong correlations between operating variables and mass-transfer responses, suggesting technological robustness and potential for scale-up to industrial manufacture. Overall, the prebiotic pumpkin in syrup developed here can be considered a technically feasible confectionery alternative for adults with overweight, obesity, and diabetes who seek to moderate glycaemic excursions without fully renouncing sweet foods. By integrating a vegetable rich in bioactive compounds with a reduced-calorie, potentially prebiotic sweetening system, this product concept contributes to the broader agenda of designing culturally acceptable, technologically prebiotic, stable functional foods that support both metabolic and gut health.
