Valorization of Food Processing Waste to Produce Valuable Polyphenolics

Abstract

Traditional incineration and landfill of food processing waste (FPW) have polluted the environment and underutilized valuable bioactive compounds, including polyphenols in food waste. As one of the most widely occurring compounds in the FPW, polyphenols possess high utilization value in many fields such as human health, energy, and environmental protection. Extracting polyphenols directly from FPW can maximize the value of polyphenols and avoid waste of resources. However, traditional polyphenol extraction methods mostly use the Soxhlet extraction, infiltration, and impregnation method, consuming a large amount of organic solvent and suffering from long extraction time and low extraction efficiency. Emerging green extraction methods such as supercritical fluid extraction, ultrasonic-assisted extraction, microwave-assisted extraction, and other methods can shorten the extraction time and improve the solvent extraction efficacy, resulting in the green and safe recovery of polyphenols from FPW. In this paper, the traditional treatment methods of FPW waste and the application of polyphenols in FPW are briefly reviewed, and the traditional extraction methods and emerging green extraction methods of polyphenols in FPW are compared to obtain insight into the start-of-the-art extraction approaches.

Optimized Extraction of Glycosylated Flavonoids from Pepper (Capsicum annuum L.) Agricultural Biomass Residues through Ultrasonic Pulse-Assisted Natural Deep Eutectic Solvents

“…The NaDES composed of 1,6-hexanediol had a density almost equal to that of pure water at RT (Table S2), facilitating the penetration of the solvent into the complex structure of pepper biomass and the plant cell to finally solvate the metabolites. The density of the alcohol-based NaDESs is lower (1.01−1.17 g/cm 3 ) than that of carboxylic acid−based NaDESs (1.11−1.15 g/cm 3 ). This is due to the special arrangement dictated by the interactions between the HBA and HBD, mainly the formation of hydrogen bonds and van der Waals forces.…”

“…2 AB comprises leaves, stems, roots, seeds, pulp, and shells, which are usually abandoned, thrown into rivers or canals near the production areas, burned in the open air, or reincorporated into the ground. 3 All of these practices cause serious environmental and health problems and represent a lost opportunity for generating value-added products to the detriment of economic potential. These residues can be integrated into circular economies through new technologies consistent with green chemistry principles.…”

Wine Lees as Source of Antioxidant Molecules: Green Extraction Procedure and Biological Activity

“…In all cases, the cultivar Nocera Rosso guarantees the highest yields. Focusing our attention on the phenolic molecules, the wine lees represent a vegetable matrix rich in high-added-value compounds, such as flavonoids, tannins, and phenolic acids [ 25 ]. The literature has established that the chemical integrity and biological characteristics of the active molecules can be successfully preserved by employing eco-friendly procedures, considering low temperatures, reduced extraction times, and green solvents [ 26 ].…”

Comprehensive Physical and Chemical Characterization of Corncob and Nopal Fibers: Exploring Sustainable Alternatives for High-Value Applications

“…Remarkably, both nopal mucilage samples showed low levels of free phenolics and bound FA, suggesting that the overall phenolic content in these samples could be attributed to other compounds, such as eucomic acid and flavonoids like isorhamnetin and quercetin, which have been reported to be present in nopal-derived samples. 37 Chang et al mention that phenolic acids mainly exist in insoluble or combined form, while flavonoids often exist in the form of soluble glycosides; 38 therefore, a possibility is that flavonoids present in nopal samples were solubilized before the analysis was performed, while bound phenolic acids present in corn samples resisted leakage due to their chemical structure and interactions. To gain a more comprehensive understanding of the phenolic profile of nopal samples, further chromatographic analysis is needed.…”