Brazilian Mantiqueira hops: composition and potential industrial use

Why was the work done: The global cultivation of hop varieties has expanded to Australia and South America, where the environmental conditions influence their composition. A Brazilian hop variety, Mantiqueira has potential applications in brewing, but the chemical composition and industrial suitability remain unexplored. How was the work done: The composition of Mantiqueira hops was determined by extracting the bioactive compounds using three pressurised fluid techniques: supercritical CO₂ (scCO₂), pressurised propane, and a pressurised mixture of scCO₂ and ethyl acetate or ethanol. High-performance liquid chromatography was used to identify and quantify alpha acids (humulone, cohumulone, and adhumulone), beta acids (lupulone, colupulone, and adlupulone), and the key phenolic compound xanthohumol. What are the main findings: Supercritical CO₂ achieved the highest recovery of alpha and beta acids, with the seven compounds representing up to 98.9% of the extract mass. Pressurised propane selectively extracted alpha and beta acids, producing (potential) bitterness enhancing extracts with minimal phenolic content. The addition of ethyl acetate to scCO₂ as a co-solvent increased the xanthohumol concentration by over 30-fold compared to scCO₂ alone. Further, the combination of scCO₂ and ethanol enhanced the extraction of both (potential) bitter acids and bioactive compounds, with higher temperatures and pressures yielding improved efficiency and diversity of compounds. The chemical profile of Mantiqueira hops was comparable to that of the noble Czech and North American aroma hops. Why is the work important: This study characterises a Brazilian hop variety with diverse applications. The findings report sustainable extraction methods and the composition of Mantiqueira hops, which could enhance beer flavour, aroma, and quality. Additionally, the high xanthohumol content supports the use of these hops in functional foods and nutraceuticals, broadening their industrial relevance and contributing to global hop diversification.