Drying Kinetics and Quality of Foam-Mat-Dried Acerola With Plant-Based Foaming Agents

Acerola is a nutrient-rich but highly perishable fruit that requires processing to preserve its nutritional quality. Foam mat drying is an effective method for retaining nutrients in liquid and semisolid foods, provided that suitable foaming agents are selected. The use of plant-based foaming agents represents a promising solution to meet the demands of vegan and vegetarian consumers. Therefore, this study proposed to evaluate the influence of different plant-based foaming agents and drying temperatures on the quality of acerola pulp powder. Acerola pulp was dried at 60°C and 70°C using soy protein isolate (SPI), concentrate of pea protein (CPP), distilled monoglycerides (Dimodan), and lactic acid esters (Lactem), and the effects on drying kinetics, nutrient retention, and color were investigated. Process parameters affected drying rates and were associated with the powder's nutritional characteristics. The diffusion model did not provide a satisfactory fit to represent the drying kinetics, suggesting anomalous diffusivity. The Page model demonstrated a precise fit and was associated with anomalous diffusion, with its exponent unequivocally indicating super-diffusive behavior. Drying at 70°C favored vitamin C retention due to faster moisture removal, whereas 60°C better preserved phenolic compounds and carotenoids. SPI, in combination with fatty acid ester-based agents, further enhanced vitamin C retention. Notably, all powders exhibited exceptionally high vitamin C content, exceeding 10 g per 100 g. These results underscore the potential of plant-based foaming agents for producing nutritionally rich acerola powder through foam mat drying, a simple and readily applicable process for developing plant-based food products. PRACTICAL APPLICATIONS: This study addresses a simple, cost-effective, and scalable process suitable for both small- and large-scale production of acerola powder, an appealing ingredient for fortifying foods and beverages. The proposed process preserves nutritional compounds and demonstrates the viability of using plant-based proteins as natural foaming agents, either alone or in combination with plant-based fatty acid-derived emulsifiers.