Optimization of the Production of Dietary Fiber Concentrates from By-Products of Papaya (Carica papaya L. Var. Formosa) with Microwave Assistance. Evaluation of Its Physicochemical and Functional Characteristics

Abstract

A process involving an ethanol extraction step and microwave assisted dehydration was designed to produce dietary fiber concentrates (DFC) from papaya (Carica papaya L. var. Formosa) by-products. It was concluded that a 15 min extraction with 2.9 mL of ethanol/g of papaya pulp followed by drying performed at 40C, produced DFC with optimal values for functional properties (hydration properties, oil holding capacity, specific volume, water soluble fraction) as well as b* color parameter and content of phenolic compounds. The DFC obtained from papaya peel using the same conditions, showed a higher content of cell wall polysaccharides and higher glass transition temperature (38C) than the one obtained from pulp (8C) and the polyphenol content doubled the one of pulp. Both DFCs showed potential to be used for nutritional purposes as well as for technological applications as antioxidants and/or thickeners. Practical Applications: Consumer demands for more healthy food products and global policies on the issues of health and environment are the keys for the development of innovative food products with profitable markets. The conversion of by-products from the papaya industrialization to dietary fiber concentrates (DFC) with functional activity fulfills these requirements, being salad dressings or dairy products, the targets for DFC application as viscosity modifiers and nutritional value improvers.