CINÉTICA DE SECAGEM DA POLPA DOS FRUTOS DE GUEROBA (syagrus oleracea) E AVALIAÇÃO DA QUALIDADE DAS FARINHAS

Abstract

This study evaluated the drying of Gueroba fruits pulp. Syagrus oleracea (Martius) Beccari. (Gueroba) is a typical Cerrado palm tree belonging to the family Arecaceae (Palmae). In Goiás, it has synonymy of gueroba or guariroba, already in other regions of the country is popularly known as guarirova, jaguaroba, bitter palmetto, catolé, bitter coconut among others, being the pulp oil used in diets because it is rich in unsaturated fatty acids, mainly linoleic and oleic, and the almond oil indicated for industrial purposes, because it has cosmetic and medicinal properties as well as saturated fatty acids, mainly lauric fatty acid. The objective of this work was to determine the drying kinetics of the gueroba pulp in different temperature conditions (40, 50, 60 and 70 ° C in a forced circulation oven) and to adjust different mathematical models to the experimental data, as well as to obtain values in accordance with the equilibrium water content of the product. The water content was evaluated by the gravimetric method 0.125 ± 0.024 dry basis (bs), determining the centesimal composition. The drying temperature increase promoted an increase of the effective diffusion coefficient. The activation energy of the process was 18.343 kJ mol-1, where the data tested were adjusted by means of two mathematical models in order to obtain the models parameters and choose the one that are best represented in the drying curve. The best fit choice was determined by the coefficient of determination (R2) and the relative mean deviation (P). According to the obtained results, it can be concluded that: the Midilli and Logarítmic models were the ones that obtained better adjustment of the drying conditions, both were submitted to the Akaike Information Criterion (AIC) and Schwarz Bayesian Information Criterion (BIC) in order to choose one of the models to predict the drying curve of the gueroba epicarp under different conditions. Physicochemical analyzes were carried out being protein by Kjeldhal method, ash by muffle incineration, lipids in Soxhlet apparatus, pH using digital pH, where Ph obtained values were between 6.11 and 6.22, total soluble solids ( ° Brix) with refractometer, grain size and color, mineral content, total phenolic compounds, absorption indexes (water, milk and oil) and solubility index (water and milk), emulsifying activity, emulsion stability and foam. In this study, these variables that affect the texture quality, color and taste did not present differences. It is assumed that the results found are related to the fruit physiology, maturation and storage and microorganism activity that are issues that affect the characteristics investigated in this study.