Extraction of phenolic compounds from acerola by-products using chitosan solution, encapsulation and application in extending the shelf-life of guava.

Aiming the simplification of the production of chitosan nanoparticles as an encapsulating material, the primary approach of this study was to investigate the extraction of active compounds from acerola-pulp by-products directly in chitosan solution by using tip sonication. The results have shown that chitosan solution can be used as a good solvent, mainly for total phenolic compounds (TPC) extraction (1792.7 mg/100 g of dry by-product). The extract was submitted to ionic gelation process using, as counter-ion, the sodium tripolyphosphate to form loaded nanoparticles with TPC. The suspension was applied as protective coatings on the guavas. The nanoengineered coatings provided an effective barrier that delayed the maturation and maintained the green pigmentation for longer periods along with good firmness. To the best of our knowledge, this was the first study that uses chitosan solution as extraction solvent of TPC from food byproducts in order to facilitate the encapsulation process.