Iron-Fortified Pineapple Chips Produced Using Microencapsulation, Ethanol, Ultrasound and Convective Drying

Abstract

The present work proposes using microencapsulation, ethanol, ultrasound and convective drying to obtain iron fortified pineapple chips. Iron microparticles were produced by ferrous sulphate encapsulation with maltodextrin by spray drying. As a hydrophilic material, microparticles were dispersed in ethanol to be incorporated into the pineapple tissue, with or without the application of ultrasound. Then, the effect of different pre-treatment times with ethanol and ethanol + ultrasound was evaluated on pineapple drying. Finally, the residue of ethanol was evaluated in the final products. Pre-treatment with ethanol and ethanol + ultrasound allowed to increase significantly the iron content of pineapple chips (up to 1000% in comparison with control). In addition, the drying time decreased from 35.4 to 51.9% with the utilization of ethanol and ultrasound. Pre-treatment for 7.5 min allowed to reduce the drying time and to achieve negligible residual ethanol in the sample. The results demonstrated that the combination of the proposed technologies can be used to obtain pineapple chips enriched in iron, with reduced time of drying and a negligible residue of ethanol.