Miao 俨龙 What data have you been looking at that shows GABA in beer? From what I understand, GABA is not present in beer but other components (derived from hops) can have effects on GABA in the CNS. Ethanol, on the other hand, does not affect GABA levels but acts on GABA-receptors.

Article Recent Trends In The Determination Of Biogenic Amines In Fer...

I could not believe there was actually an answer when I found it! Was about to reply that "it probably would be too technically demanding to be practical," but I guess the brewing industry needs to know.

Hope that helps.

Miky Timothy That paper is very interesting, but GABA is not a biogenic amine. Those include serotonin, norepinephrine, epinephrine, dopamine, and histamine. But given the effect of biogenic amines on the CNS, it's certainly relevant!

Angela P Taylor, Serotonin, norepinephrine, epinephrine, dopamine, and histamine are all monoamine neurotransmitters/neuromodulators/hormones. This group is a subclass of cyclic amino acid derivatives with a terminal ethylamine moiety, though there is an n-alkyl substitution in the case of epinephrine. In terms of organic chemistry, they are in the same class for a variety of reasons, namely because they are products of complete decarboxylation and thus are all bases. GPCR binding characteristics (one 5-HTR exception) are another reason these are grouped together in contrast to classical neurotransmitters.

GABA is a non-proteinogenic amino-acid and is itself a decarboxylation derivative of the acidic amino acid glutamate. As a zwitterion, it is not a base and thus is technically not an 'amine'.

Melatonin likewise would probably not be considered a biogenic amine because it is an amide derivative of serotonin.

Acetylcholine is altogether an oddball - a quaternary ester derived from dietary phospholipids.

Neuroscience textbooks tend to dwell on a pedantic taxonomy of 'biogenic amines', simply as an exercise in categorization without actually providing much functional insight. The chemical characteristics of neurotransmitters are fascinating and can provide some insight into how the diverse biochemical characteristics of these molecules contribute to homeostatisis (for example reuptake of serotonin vs extracellular breakdown of acetylcholine). However, the criteria for grouping 'biogenic amines' is arbitrary, in my opinion.

None of this changes the fact that the article I linked to does have references to the analysis of GABA content in beer and should be a useful resource in answering the original question - it is a very extensive review.

It is also worth noting that dietary GABA intake does not appear to have any really overt neurophysiological activity, owing to multiple factors that make endogonous neural ligand supplementation relatively ineffective, in general. The blood-brain-barrier would be a major consideration, especially at the comparatively small amounts found in food.