A new open-access paper on barley-based gluten-free beer has just been published online by the journal Food & Chemical Toxicology. I’ll briefly summarise what I can understand of its content below, but if you want it in its full, in-places highly technical glory, you can read it here.
Before I do that, a reminder that I have a list of barley-free gluten-free beers on this site, featuring ales, lagers and brews made with grains such as sorghum, millet, rice, corn and quinoa.
You may also like to check out the Instagram page NGCIbeers (not mine) which is devoted to barley-free beers.
What does the paper say?
The title of the paper asks whether gluten-free barley beers are “a blessing or an uncontrollable risk” — neither option of which strike me as particularly appropriate here — but the content, while sometimes challenging for the lay reader like myself, does offer an excellent summary of where we are on this subject: of what we know, and what we do not know.
Here are my ten key points taken from it:
1/ Beer made from barley is not gluten-free, but if treated with enzymes to ‘degrade’ the gluten, that gluten can be reduced to a point where the beer tests below the 20 parts per million (20ppm) of gluten required to achieve ‘gluten-free’ status in the EU and UK, and be deemed safe by authorities.
2/ But that 20ppm figure was based on research into solid foods and typical dietary intakes, and not drinks. It was, essentially, a compromise between feasibility and health — an achievable target for manufacturers for production and control, while maintaining safety for the vast majority of coeliacs.
3/ However, “the reliability and accurate quantification of gluten in hydrolysed products such as beer, using current analytical methods, is under debate” — or more bluntly, there is a lot of concern about whether the analytical tests used for beers pick up all the gluten / gluten fragments present after enzyme treatment.
4/ The US authorities aren’t convinced: “gluten-free” beers in America must be made from non-gluten-containing cereals, but barley-beer brewers can use the expression “gluten reduced” if they use enzymes, provided other conditions are met. (Same in Canada, Australia, NZ and I believe Argentina.)
5/ A more accurate (and expensive) gluten detection method is mass spectrometry, and this method has revealed that GF-labelled barley beers may contain gluten fragments in them with the potential to cause problems to those with coeliac disease, as they have been shown to ‘bind’ to gluten antibodies in the laboratory.
6/ However, we don’t know whether or to what extent this would replicate in the actual gut of a patient with CD. Simulated digestion models have found that, in theory, the gut may be able to further digest and drastically reduce those toxic fragments.
7/ The detection and quantification of gluten in foods and drinks is difficult because gluten fragments come in multiple complex varieties, and tests cannot possibly be designed to pick all of them up; not all potentially toxic fragments have been identified, finding them all with confidence in beer is particularly problematic, the clinical relevance of many is uncertain, and coeliacs are likely to vary with regards to the quantity and types of fragments which will trigger a reaction.
8/ In summary, we cannot know …. or, as the paper’s authors put it more formally: “Based on current knowledge it is difficult to assess whether barley-based gluten-free beer is safe for consumers with coeliac disease.”
9/ Moving forward, the authors recommend in vivo studies using isolated beer protein fragments given to coeliac patients (which researchers may be reluctant to undertake).
10/ They also recommend the “Development of standardised gluten-free production strategies to minimise variability in resulting gluten fragments”.
Should we follow the US?
Many coeliacs drink GF-labelled barley beer and feel they tolerate it just fine; while others feel they react, and others avoid it due to the concerns raised here. The varying experiences of CD patients do support the view that the picture could vary greatly, and therefore be fiendishly difficult to pin down with research. It may not be possible to reach a point where standard advice can be dispensed to all.
I’m unclear how we have reached this point, where barley-based GF-labelled beer is so popular, widely available, and deemed acceptable in the coeliac diet, in the apparent absence of any strong supporting body of research, and with other countries taking a more conservative position.
There is obviously deep doubt on this issue, and it feels to me that the expert authors of the paper may now be worried, and be laying the ground to take us in a new direction. It’s surely now fair to question why coeliacs are not being more explicitly warned of the uncertainty, when they are normally advised to take a highly precautionary stance with other matters subject to similar such uncertainty, such as “may contain traces of gluten” labelling, cross-contamination and eating out.
Could it be simply a case of wanting to maintain the status quo while the research is undertaken, thereby avoiding the potential scenario where we switch to the US position and then have to reverse ferret when the research finds that everything is OK after all?
But … how much time will we have wasted if it isn’t OK after all? And what damage to the health of coeliacs may have been done in the meantime?
