Biopolymers to overcome challenges in açaí pulp drying: Processing and powder quality evaluation

Abstract

The production of stable açaí powder by affordable drying methods is challenging due to its high unsaturated lipids and anthocyanins content. This study assessed the effect of adding pectin, maltodextrin, and gum Arabic at a low concentration on the processing of açaí pulp and the powdered product quality obtained by cast-tape drying, an energy-efficient drying technique. The pectin-containing sample had the highest linear viscoelastic range and flow point, contributing to the film-forming during drying and the powder quality. Pectin hindered oil separation during drying, as shown in micrograph images and CLSM, and the dried açaí-pectin material was effortlessly removed from the support. FTIR spectra indicated physical rather than chemical interactions between açaí and pectin. Moreover, adding pectin resulted in a powder with anthocyanin content and antioxidant activity like freeze-dried products. This study demonstrates that a small biopolymer concentration is a technological solution for obtaining high-quality açaí powders by cast-tape drying.