Beneficiamento da casca de jabuticaba em leito de jorro

Abstract

Fruit consumption has increased over the years and consequently the generation of waste which is mainly composed of fruit peels as a result of the domestic and industrial processing. Overall, these residues are discarded, but they can have interesting characteristics such as the jabuticaba peel that has a high quantity of phenolic compounds, for example, the anthocyanins which have antioxidant capacity. Therefore, in order to exploit its characteristic, the present work has as the objective processing of the jabuticaba peel during the spouted bed drying at two temperatures (60 e 70°C) with the analysis of quality parameters, for instance, the degradation kinetics of anthocyanins. The pH differential methodology was used to determine the anthocyanins content at defined time periods during the drying. With the kinetic data, it was possible to infer the order reaction (first order), kinetic constant (0.009 and 0.023 m-1), D value (255.84 and 100.11 min), half-life time (77.02 and 30.14 min), and activation energy (89.19 KJ/mol) for the temperatures 60 and 70°C, respectively. A mathematical model was developed based on macroscopic balances of mass and energy that describe the drying performance. The model consisted of four ordinary differential equations (moisture and temperatures of solid and gas) and was implemented in Matlab® 7.10. The quality criteria of adjustment for moisture: R2 (0.9856 and 0.9752), MSE (0.0203 and 0.0345), Af (1.0829 and 1.2046), and Bf (0.9724 and 0.8802) for the temperatures 60 e 70°C, respectively, show that the model has a considerable capacity of prediction. Furthermore, the first order kinetic equation for anthocyanins was also implemented. With the data generated by the model, it was possible to calculate the kinetics parameters, and a comparison with the experimental dada through the percentage error was done obtaining the best results for 70°C.