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Biogenic amines in spontaneously fermented beers are produced mostly by enterobacteria, but lactic acid bacteria and yeasts can also produce them. Wort that is pre-acidified greatly reduces the production of biogenic amines, but small levels can still be found. These levels are below the levels found in cheese and fermented sausage and are well below the levels that are acceptable for health (histamine levels less than 50 mg/kg in the US and less than 400 mg/kg in the UK; these levels are usually regulated for meets and fish<ref">[https://www.mdpi.com/2304-8158/8/2/62/htm Impact of Biogenic Amines on Food Quality and Safety. Claudia Ruiz-Capillas and Ana M. Herrero. 2019. DOI: https://doi.org/10.3390/foods8020062.]</ref>). De Roos et al. (2018) measured biogenic amines over the fermentation lifespan of Belgian lambic beers that were pre-acidified to a pH of 4.5 before being cooled in a coolship and spontaneously fermented. They found that the initial wort had low concentrations of some biogenic amines, such as agmatine (9 mg/l), putrescine (8 mg/l), and cadaverine (3 mg/l). In one cask, the agmatine remained stable while in the second cask the agmatine declined to zero during the maturation phase, and then slightly increased to less than 5 mg/l. Cadaverine was produced during the first three weeks of fermentation and remained steady throughout the fermentation process at about 30 mg/l. Histamine was produced during the acidification phase by ''Pediococcus damnosus'' between 3 and 9 months and ended up at around 15 mg/l. Tyramine had final concentrations of around 30-40 mg/l and was formed either during the acidification phase (6 months) or the late maturation phase (18-24 months), potentially by ''P. damnosus'' or some other LAB that was at too low of a population to detect, or maybe as a result of autolysis of dead yeast cells. 2-Phenylethylamine and tryptamine were never found in the lambic beers <ref name="Roos_2018_2" />.