Content area
Abstract
The pulsed electric field (PEF) is a non-thermal food processing technology that induces electroporation of the cell membrane, thus improving mass transfer through the cell membrane. The present study aims to evaluate the influence PEF intensity on the drying of mango peels at different temperatures. Mango peels were subjected to PEF at an intensity of 1.5, 3.0 and 4.5 kV cm−1, frequency of 10 Hz and total time of 600 µs and dried at temperatures or subjected to drying at 50, 60 and 70 °C at an air velocity of 1.0 m s−1. An evaluation was made of the influence of PEF intensity and drying temperature the thermodynamic properties, physical properties (water activity, hygroscopicity and solubility), temperature glass transition (Tg), total phenolic compound (TPC), antioxidant activity (DPPH, ABTS and FRAP), and starch digestibility (in vitro). The efficiency of PEF was verified, especially when applied to 4.5 kV cm−1 and dry at 70 °C, where the maximum reduction in drying time reached 67%, followed by the lowest degradation of TPC (24.30%), and higher solubility (78.478%) and Tg (59.97 °C). In addition, for this same condition, the antioxidant activity by the DPPH method showed the highest values (69.27 and 176.21 μmol Trolox/g) and at 120 min the digestibility was 26.04%. The results show that the use of non-thermal technologies in the pre-treatment of agro-industrial residues is viable for the drying process.