Xanthohumol properties and strategies for extraction from hops and brewery residues: A review

Xanthohumol, a chalcone unique to hops, has attracted attention from researchers due to its several pharmacological effects on humans. In industry, hops are almost exclusively used in beer production, generating tons of solid waste - hot trub from the boiling step and spent hops from the dry hopping - rich in biocompounds, among them xanthohumol, that could be recovered and used for several nutritional purposes. The literature is extensive on extraction processes of xanthohumol directly from hops, but only a few studies present its recovery from brewery solid waste. We focus on presenting the xanthohumol characteristics and benefits for human consumption, and discuss the main extraction techniques, their advantages and limitations, to prospect strategies to recover this high-value compound from brewing solid waste. Recent extraction processes represent promising approaches to overcome the limitations of conventional methods, but further studies are still needed to understand xanthohumol extraction and purification and induce industrial upscaling.