Valorização de resíduos de frutos de Dipteryx alata Vogel para aplicação tecnológica em alimentos: estudo de extratos bioativos e filmes nanoestruturados

Abstract

The growing environmental concerns and the pursuit of sustainable materials motivated this study, which aimed to explore the potential of baru residues in the production of active biodegradable starch-based films reinforced with nanocellulose and plant extract derived from the fruit itself. The research evaluated the bioactive and chemical properties of the baru pulp and endocarp, highlighting their applications in sustainable packaging. The baru pulp exhibited a high concentration of bioactive compounds, notably trigonelline (139.10 mg 100 g⁻¹), tannins (429.16 mg TE 100 g⁻¹), and the phenolic acids trans-cinnamic (5.91 mg 100 g⁻¹) and quercetin (5.98 mg 100 g⁻¹). Industrially relevant sesquiterpenes, widely used in essential oils, composed 82.05% of the pulp's volatile profile, with α-copaene and bicyclogermacrene as the main components. This volatile profile gives the pulp a predominantly woody aroma with herbal nuances, broadening its potential applications in fragrances. In parallel, the baru endocarp was utilized to obtain lignocellulosic micro- and nanofibrils (LCMNF) through alkaline pretreatment and mechanical refining, which were incorporated into the film formulations. The films were prepared using corn starch as the polymeric matrix, reinforced with LCMNF and hydroalcoholic extract of baru pulp as a source of bioactive and antioxidant compounds. The ACE6 films, with the highest extract concentration, exhibited a high total phenolic content (521.78 mg GAE/g) and enhanced antioxidant capacity in the phosphomolybdenum (81.7 mg AAE/g) and DPPH (24%) assays. This increase in extract concentration reduced the films' hydrophilicity (contact angle of 79.58° in ACE6), but compromised tensile strength (26.34 MPa) and water vapor permeability (WVP of 178.61 g/m²·day). The combination of lignocellulosic micro-/nanofibrils and baru extract in the starch matrix improved the films' thermal stability and structural functionality, as confirmed by thermogravimetric analysis (TGA) and Raman spectroscopy. The results indicate that the developed films have potential as antioxidant coatings for food packaging. The valorization of baru byproducts represents a sustainable and innovative approach, promoting the integral use of fruit residues. This research reinforces the commercial and ecological viability of baru, contributing to eco-efficient technologies in the food sector