Craft beers: how brewing styles and ingredients influence biogenic amines content in commercial samples

Biogenic amines (BAs) are nitrogenous compounds naturally formed during fermentation and are increasingly recognized as emerging chemical hazards in fermented beverages. Craft beers, usually unfiltered and unpasteurized, offer conditions favourable to BAs formation. This study provides a comprehensive assessment of seven BAs in 113 craft beers available on the market, categorized by fermentation type: bottom, top, spontaneously fermented beers and mixed style. Additionally, the influence of unconventional raw materials and brewing techniques was assessed. Results showed that there was a wide variation in the total BAs content, ranging from 1.64 to 280.08 mg/L. The main BA detected was tyramine, followed by tryptamine, putrescine and cadaverine. Bottom-fermented beers did not show harmful concentrations of tyramine, whereas higher concentration of this molecule has been detected in other beer styles. Barrel aging, bottle re-fermentation and the addition of unconventional ingredients caused a higher accumulation of tryptamine, spermidine and particularly of tyramine. Notably, histamine was detected above the quantification limit in 98 samples, raising concerns for histamine-intolerant consumers. On the whole, 10% of the beers under investigation could cause negative physiological effects for healthy consumers, showing a total BAs content above 50 mg/L. However, 35% of the examined craft beers had a total BAs above 20 mg/L, resulting in a potential health hazard for consumers with low BA-detoxification capacity. These findings highlight the need for optimized hygiene practices, careful raw material selection and eventually the use of BA-degrading starter cultures, to ensure consumer safety without compromising product identity.