Microwave-Assisted Glycerol-Based Extraction of Bioactive Compounds from Defatted Hass Avocado Cake: Process Optimization, Chemical Characterization, and Sustainability Assessment
Luane Souza Silva Lage, Beatriz Pereira de Freitas, Carolline Margot Albanez Lorentino, Thayssa da Silva Ferreira Fagundes, André Luis Souza dos Santos, Davyson de Lima Moreira, Eliane Przytyk Jung, Suely Pereira Freitas, Leilson de Oliveira RibeiroAbstract
Avocado processing generates substantial agro-industrial residues with potential as sources of bioactive compounds. This study investigated defatted cake obtained from continuous-press oil extraction of Hass avocado pulp and peel as a feedstock for bioactive recovery. Microwave-assisted extraction using glycerol as a solvent was optimized through experimental design by varying glycerol concentration (40–90%), temperature (70–170 °C), and extraction time (7–23 min). Optimal conditions (170 °C, 70% glycerol, 7 min) produced significantly higher total phenolic content and antioxidant capacity than conventional extraction (p < 0.05). UPLC-HRMS/MS analysis enabled the putative identification of 55 compounds. Toxicity assessment using Galleria mellonella indicated low toxicity at 1033 mg GAE L–1. Sustainability evaluation using the Path2Green metric yielded a score of 0.595, demonstrating favorable environmental performance. These results highlight microwave-assisted glycerol-based extraction as an efficient and sustainable strategy for avocado byproduct valorization.