Valorization of Red Pitahaya (Hylocereus sp.) Peel Through a Multi-Product Cascade Biorefinery Approach Towards Bioactive Food Packaging Films

• Published in: Food biophysics 2025-03, Vol.20 (1), p.24, Article 24
• Main Authors: Arroyo-Esquivel, Laura, Rincón, Esther, Jiménez, Víctor M., Vásquez, Fabian, Esquivel, Patricia, Espinosa, Eduardo, Rodríguez, Alejandro
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Antimicrobial agents; Antioxidants; Biological activity; Biological and Medical Physics; Biophysics; Biorefineries; By products; Carbohydrates; Cellulose; Cellulose fibers; Chemistry; Chemistry and Materials Science; Contact angle; Dietary fiber; Dietary minerals; Food; Food packaging; Food Science; Fractions; Fruits; Hylocereus; Leptocereus quadricostatus; Lignin; Mechanical properties; Pectin; Polymer blends; Refining; Tensile strength; Thermal stability; Ultraviolet radiation; Water vapor; Wettability
• ISSN: 1557-1858; 1557-1866
• DOI: 10.1007/s11483-024-09907-w

This study proposes efficient valorization of red pitahaya ( Hylocereus sp.) peels by separating and purifying their structural and bioactive fractions to produce bioactive films through a multi-product cascade biorefinery approach. The process begins with the extraction of a betalain-rich extract (BET), followed by the separation of pectin (PEC), and finally, the production of cellulose nanofibers (CNF) from the remaining residue. The entire cascade process resulted in a successful utilization of 79.5% of the pitahaya peel. All fractions obtained were integrated into PEC-based films reinforced with CNF in the following proportions 5, 15, 30 and 45% CNF. The films were subsequently subjected to characterization in terms of their physical, chemical and mechanical properties. The optimal mechanical reinforcement effect was observed in films with 45% CNF, which exhibited an increased tensile strength of 20.47 MPa compared to 100% PEC, and higher thermal stability. Therefore, the ratio of 45% CNF was selected for the addition of the bioactive fraction, which comprised 5, 10, 15, 20, 30, 40 and 50% BET. In general, all bioactive films exhibited a compact and uniform structure. Films with higher percentages of BET showed a decrease in water vapor barrier properties (50-70% increase in water vapor permeability), probably due to the hydrophilic nature of BET. Additionally, the inclusion of BET resulted in enhanced wettability, as evidenced by a reduction in water contact angles (36.36º). The UV light blocking capacity increased (57% increase) while transparency decreased (43-50%) with the addition of BET.