Data published in Cosmetics indicated that waste yeast from the brewing process often contained higher antioxidant levels than the starting material, showing that the microorganisms absorbed polyphenols during the brewing process. And these waste yeast extracts, along with spent hops extracts, were effective in improving measures of skin aging.
“This study offers evidence that beers become enriched in phenols from their ingredients, and that brewing products and waste are interesting sources for the preparation of dietary supplements and cosmetics,” wrote scientists from the University of Camerino, Recusol srl, and the University of Bologna in Italy.
“This study shows the anti-aging effects of waste products from handcrafted beers in human keratinocyte cells, suggesting their potential use as ingredients for the preparation of cosmetics.”
The market for craft beer has grown over the past decade, although sales did decline in 2020, according to the Brewers Association. Despite this, craft beers still account for over 12% of the US beer market by volume, states the association.
The industry represents an interesting source for by-products that could be upcycled for ingredients for cosmetics and/or dietary supplements, stated the Italy-based scientists behind the new study.
The study set out to evaluate the phenol content and antioxidant activity of various Italian craft beers, including lager, amber, triple malt, red, and black. The researchers also tested the starting materials (malts, hops, and yeast), the intermediate products, and the waste products (spent malts, hops, and yeast). Then, using human keratinocytes, they tested the waste extracts from the amber beer for their biological activity.