Characterization and evaluation of flour's physico-chemical, functional, and nutritional quality attributes from edible and non-edible parts of papaya

Abstract

Papaya fruits different edible and non-edible portions are valued for the abundance of numerous nutrients and therapeutic benefits. The study was aimed to examine the physico-chemical properties, bioactive compounds (total phenolics and total flavonoids), antioxidant activity and microstructure analysis of the peel, pulp and seed flour of both ripe and unripe papaya. The results demonstrated the different portions of both ripe and unripe papaya fruit flour differed significantly with respect to almost all quality attributes within them. The physico-chemical variations have been evaluated through evaluation of the pH, moisture content, TSS, and ascorbic acid content of the papaya fruits during both ripening stages. Statistically significant variations (p < 0.05) were observed between two distinct stages of ripening. The concentration of ascorbic acid in the fruit revealed a notable increase as it matured, while the pH, moisture, and TSS all exhibited a substantial decrease (p < 0.05) during the immature stage. The unripe peel showed the most significant level of bulk density, tapped density, swelling capacity, crude fiber, and TFC whereas the unripe seed showed the highest value of ash, crude fat, and TPC. For the rest of the value, ripe pulp and seed flour showed a significantly higher value than others. The total phenolic content in seed flour and the total flavonoid content of peel flour were 196.9 ± 0.03 and 164.9 ± 0.08 mgQE/100 g, respectively, at unripe conditions. An immense amount of antioxidant activity was found in ripe (20.48 ± 0.54%) and unripe (16.05 ± 0.32%) peels flour. The flour granules' diverse morphological forms and particle sizes were identified by SEM analysis. The versatility of papaya and its various components provides opportunities for applications in the food, pharmaceutical, cosmetic, and agricultural industries. The papaya fruit flour of different portions have unique functional, nutritional, and morphological characteristics that may contribute to the development of gluten free flour based value added baked products.