Review: Stability of phenolic compounds during beer processing and alternatives to increase their biovailability

Studies on antioxidants, especially phenolic compounds from beer and beer raw materials, have been increasingly explored, as phenolic compounds play an important role in human nutrition and health. This review provides an overview of the influence of malting and fermentation on the overall phenolic content from the barley malting process to the final beverage. Beer phenolics are mainly sourced from barley malt because of its proportion used in brewing beer, and can be found in both free and agglomerated forms, in concentrations up to 50% lower compared to sweet wort. Bound phenolics are released during malting, leading to an increase in free phenolics in the sweet wort. The phenolic content of the wort increases during the mash and hop stages. The wort boiling and fermentation stages are responsible for significant phenolic losses, as is the clarification and stabilization of beer made with polyvinylpolypyrrolidone (PVPP). Special yeasts, manipulation of enzymatic activity, dry-hopping, enrichment with xanthohumol and use of dark malts are alternatives to increase bioavailability in beer, benefits both for its stability and for the health of the consumer.