Characterization of the dietary fiber obtained from chayote Sechium edule (Jacq.) Sw. var. virens levis

Abstract

By-products from fruits and vegetables provide an alternative source of dietary fiber with unique properties. Chayote (Sechium edule (Jacq.) Sw.) is a herbaceous plant considered a weed in some regions, wasting its potential use in the formulation of fiber-rich foods. This research aimed to characterize the dietary fiber from the pulp and peel of Sechium edule (Jacq.) Sw. var. virens levis dried by convective drying at different temperatures (40, 50, and 60 °C). The behavior of the oven-dried pulp and peel of chayote was studied using four thin-layer drying models (Newton, Page, Henderson & Pabis, and Midilli et al.), based on the coefficient of determination (R²) and chi-square (χ²). The total dietary fiber (TDF) content for the chayote pulp and peel was determined through proximate analysis. The Page and Henderson & Pabis models were the best suited for the drying data, with the greatest R² and lowest χ² value compared with the other models. The diffusivity coefficient increased as temperature increased, and was greater in the pulp than in the peel, with an activation energy of 83.92 and 45.071 kJ mol^-1 for the pulp and peel, respectively. The best drying temperature was 40 °C, showing TDF content of 20.62 and 63.92 g/100 g db, along with functional properties of water holding capacity of 19.16 and 9.41 g/g db, oil adsorption capacity of 6.95 and 6.16 g/g db, and swelling capacity of 8.33 and 4.00 mL/g db for the pulp and peel, respectively. These results suggest that both tissues are good sources of dietary fiber.