Comparative assessment of physicochemical, structural and functional properties of dietary fiber extracted from mango (Mangifera indica L.) and soursop (Annona muricata) peels

The potential of soursop, a less well-known tropical fruit, was assessed as a source of dietary fiber (DF) and compared to mango. After optimizing the conditions to maximize the extraction yield of soluble and insoluble DF, their structural, physicochemical, and functional properties were evaluated. The results showed that soursop excelled in total and insoluble DF content (50 % higher than mango). The antioxidant response and reducing sugar content obtained for soursop were significantly higher than in mango. Yet, the insoluble fraction in both fruits was characterized by higher antioxidant activity and phenolic content. The chemical composition of both fruits revealed that glucose and potassium were the main sugar and mineral, respectively. Lactic, formic, and acetic acids were the main short-chain fatty acids produced after in vitro colonic fermentation with Lacticaseibacillus casei and Lacticaseibacillus rhamnosus, and negligible amounts of butyric, propionic, and valeric acids were detected after 48-h-fermentation, independent of the fruit. Soursop is a promising rich source of DF that can be used together with mango to develop and enhance foods' textural and nutritional characteristics.