Compostos fenólicos totais e atividade antioxidante da casca do fruto do mandacaru (Cereus jamacaru) em pó obtido em secador de leito fixo.

Abstract

Mandacaru (Cereus jamacaru) is a native brazilian plant, which is present in a large quantity in the northeastern region of the same country. their fuits are sources of phytonutrients which are very important for health, because they contain a high phenolic content and a high antioxidant activity, especially in the peel, which contains more quantity of these compaunds than the pulp.Once its fruit is perishable, with a short lifespan, it is relevant to demonstrate existing advantages in the development of alternatives to minimize its waste, being drying an option to be used in the conservation of these fruits. Thus, the objective of this work was to evaluate the effect of drying at different temperatures on the content of phenolic compounds, their antioxidant activity, as well as the physico-chemical characteristics of the mandacaru fruit peel.The drying was carried out at temperatures of 50 ° C, 60 ° C and 70 ° C, with a 1.2m/s air velocity in a fixed thin bed dryer. The analyzes were done for both the in natural material and the powder obtained after drying, mainly in the maintenance of total phenolics and antioxidant activity. The results showed there was a concentration of all nutrients evaluated after the drying process. The drying kinetics curves were represented by the empirical Page and Henderson & Pabis models, adjusting well to the experimental data, with correlation coefficients close to 1. For the diffusion model applied to a spherical geometry, values for the diffusivity coefficient of 9.17x10-11, 1.42x10-10 and 2.39x10-10 m²/s were obtained for temperatures of 50, 60 and 70 ° C, respectively. The relationship between the effective diffusion coefficient and the drying temperature can be described by the Arrhenius equation, showing activation energy for the liquid diffusion on drying of 44.05 KJ / mol.