Gluten Reduced vs Gluten Free

From Zero Tolerance Gluten Free Homebrew Club
Jump to navigation Jump to search

Note Note to consumers, distributors, retailers and hospitality managers:
Gluten reduced beer made from barley, wheat, and/or rye is not gluten free. Misrepresenting the two as equivalent puts the health of celiac consumers at risk and potentially violates labeling and advertising laws in your country. Gluten reduced (aka gluten "removed") beers can still cause short and long term damage for people with celiac disease. Further scientific review indicates that testing for residual gluten in these beers (the <20ppm reference) looks at a narrow band of proteins and is an inaccurate and unreliable indicator of their actual gluten content. The types and amount of remaining intact protein chains can vary widely between barley lots and individual beers. Individuals respond uniquely to those remaining protein chains. Gluten free beer sold in the US, Canada, Australia, New Zealand and Argentina can only be made from naturally gluten free grains and celiac societies in those countries have made clear that individuals with celiac disease should avoid gluten reduced beers made from barley and other gluten containing grains. See List of GF breweries for beers in your region that are safe for those with medical reasons to avoid gluten. Shelf and menu labeling that equates gluten reduced with gluten free is false advertising that puts the health of customers at risk.

Definitions and Background

Naturally gluten free beer: Gluten free brewing best practice

What makes a beer gluten-free? Simply put, a gluten-free beer is one made only from ingredients that are originally and naturally free of gluten. In Argentina, Australia, Canada, New Zealand and the United States this distinction is regulated by law. The "Zero Tolerance" gluten free brewing group name is a reference to a zero ppm target using 100% naturally gluten free ingredients.

Gluten "reduced" / "low gluten" beer

Gluten Reduced Beer Cheat Sheet.png

Gluten-reduced (also sold as “Crafted to remove gluten” or, less accurately, "Gluten-Removed" or "Deglutinized") beers are made from gluten containing grains (generally barley) and typically use a prolyl endopeptidase (PEP) enzyme (Clarex or Clarity Ferm) to “hydrolyze” (break down) proteins. (Other less common hydrolyzing methods include silica gel, tannins or ultrafiltration). Examples of "gluten reduced" beers include Omission (US), Category 12 “Breakthru” (Canada), Daura Damm (Spain), Mongozo (Belgium), Celia Lager (Czech Republic), St Peter's (UK -- previously gluten-free now barley-based gluten-reduced), and Wold Top Against the Grain (UK). Most "gluten free" beers brewed in the UK are actually barley-based "gluten reduced" beers. Note that the terms "gluten removed", "gluten reduced", "deglutinised", or "low gluten" are regulated by the food and drug labeling regulations of individual countries. Some of those terms may be prohibited in one country but not in another. The term "gluten removed" suggests a total absence of gluten that is not accurate.

Gluten reduced beers appeared in the first decade of the 21st century as a product application offshoot of the PEP enzyme developed to reduce protein haze in conventional (barley-based) beers. In some locations (Europe and the UK especially) gluten reduced beers have proliferated given the following factors:

  • A low barrier to entry for employing this method (adding a vial of liquid enzyme at the start of fermentation to an otherwise identical barley-based beer), making this an easy and cheap approach
  • Lack of a gluten free malt supply chain, especially outside of North America
  • In contrast to North America, Australia and New Zealand, no changes to labeling legislation to provide consumers with better transparency (and hence no commercial incentive for brewers to use naturally gluten free ingredients)
  • Limited to no advocacy on the part of European coeliac associations for better gluten free beer standards; reliance on outdated testing methodology for determining beer safety (see below)

Using PEP enzymes to hydrolyze and reduce protein chains in beer is neither "cutting edge" nor best practice. It's a hold-over in the absence of better infrastructure (and support) for naturally gluten free brewing using hiqh quality ingredients (especially malted grains) and evolving techniques for brewing with them.

Low gluten barley

While the vast majority of gluten reduced beers are made by hydrolyzing enzymes added to conventional barley worts, there has been some plant breeding work to develop strains of barley that have naturally lower gluten protein content. Kebari is the registered trademark name for a low gluten barley developed by CSIRO (the Commonwealth Scientific and Industrial Research Organisation), an Australian government agency.[1] The breeding program took separate lines of barley that each had low or null levels of hordein-B, -C, and -D gluten protein families. Through conventional breeding practices they then selected crosses that had null levels in all three hordein classes. A fourth hordein family (y-hordein) contributes some residual gluten (which they measure at <5 ppm). Researchers reported somewhat smaller grain size, lower yield relative to other barley varieties, normal alpha-amylase levels, low beta-amylase levels, and high fan levels.[2] [3]

To date, adoption of this low gluten barley has been slow. As an offshoot of the CSIRO work, German brewery Raderberger began using Kebari for a new gluten free pilsner product in 2016, though it appears that this beer is no longer being brewed. In countries with food labeling regulations that prevent beer made from barley being labeled "gluten free", Kebari-based beers would face that labeling challenge. Other potential adoption challenges globally could include consumer preference for zero gluten brewing grains, aversion to introducing a low gluten product by dedicated gluten free brewer, and concerns about cross-contact between low-gluten barley and conventional barley, wheat and rye grains in non-dedicated breweries and malt houses.

Key issues with the gluten-reduced approach

A protein depicted as a long unbranched string of linked circles each representing amino acids
A polypeptide is an unbranched chain of amino acids

Proteins are comprised of long chains of repeating units (amino acids). Gluten proteins are found in barley, wheat, or rye and contain more proline and glutamine, two amino acids - and hence often called "prolamins". The presence of these amino acids makes gluten harder to digest. "Gluten" is the umbrella term for these proteins and have different names in wheat (gliadin and glutenin), barley (hordeins) and rye (secalins). A common feature of gluten proteins is that they are made up of different repeating patterns (epitopes) of amino acids. Some of these epitopes are not broken down by digestion in the body and react with the immune system to cause symptoms and illness. These are referred to as immunogenic epitopes.

While the fermentation process naturally leads to some fragmentation of gluten and other types of proteins, the amino acid patterns (epitopes) that cause problems for celiacs are generally non-soluble and resistant to digestion. Prolyl endopeptidase (sometimes called prolyl endoprotease, or PEP, or AN-PEP) is an enzyme originally patented to reduce chill-haze in beers. This enzyme that can cut proteins at prolines, has been used with the intent of reducing "gluten content" of barley-based beers by targeting and breaking down some of these protein chains (hydrolysis). There are two key problems with this approach:

Proteins in gluten reduced beer are fragmented not eliminated: celiac reactive immunogenic epitopes can remain intact

While these PEP enzymes create smaller protein fragments, they do not "destroy" or "remove" all gluten and celiac-related epitopes have been detected in beer that uses these enzymes and processes. Protein fragments responsible for the celiac autoimmune response (i.e. that contain immunogenic epitopes) may remain intact, as have been detected by LC-MS testing, western blot analysis, lateral flow immunochromatographic assays (LFIAs), and in vitro testing with celiac antibodies.[4][5][6][7]

There are dozens if not hundreds of gluten-related epitopes (amino acid patterns) that can trigger the autoimmune response in celiac individuals.[8] The Immune Epitope Database currently lists 1164 records related to CD.[9] Individuals respond differently to different classes of gluten, including those found in beer made from gluten containing grains. Moreover, different types or batches of beer will contain different proteins/epitopes and individuals will respond differently. In practice, one person with celiac disease might experience acute symptoms, another might have an asymptomatic reaction, another may not react at all. Statements on social media to the effect of "my spouse / friend / neighbor drinks gluten reduced beer without issues" fails to recognize this inherent variability of reactions.

Barriers to ELISA testing of hydrolyzed and fermented products: Significant potential for false negatives

The test employed by most commercial gluten reduced brewers, Enzyme-Linked Immunosorbent Assay (ELISA) antibody testing, looks at a narrow range of target epitopes (amino acid patterns that are frequently encountered in gluten proteins). These sequences are termed antigenic epitopes – meaning they bind to the test antibody used in the ELISA. An important distinction is between an antigenic epitope - a sequence that is detected by a test; and an immunogenic epitope - a sequence that triggers an immune response in the body. These could be the same sequence, but this is not always true. There will be many gluten fragments that will not be detected by a single indirect test method, such as an ELISA.

A gluten-containing beer treated with a PEP enzyme may register below the 20ppm threshold using ELISA if it does not detect the antigenic epitope that it is looking for, but this beer may still contain gluten protein fragments from the other celiac immunogenic (toxic) epitopes.

These limitations led to a 2020 final ruling by the US FDA that it "knows of no scientifically valid analytical method effective in detecting and quantifying with precision the gluten protein content in fermented or hydrolyzed foods in terms of equivalent amounts of intact gluten proteins."[10]

More detailed liquid chromatography / mass spectrometry testing -- as well as in vitro (lab) testing of Celiac patient antibodies -- shows that beers tested less than 20ppm with ELISA testing can in fact have widely varying residual gluten levels that negate the <20ppm threshold claim used by most brewers who use this method.[11][12][6]

Literature regarding the R5 Competitive ELISA testing method for gluten-reduced beer[13] describes the requirement for a "calibrator", as is needed in all scientific methods. However the process of brewing and additionally the use of an enzyme, results in variability: evident between different breweries, between styles from the same brewery, and arguably between batches. This is due to the different ingredients and the different processes. Thus, there is no universal standard for gluten, and certainly not for hydrolyzed gluten found in beer. The use of the competitive ELISA may provide a true positive (be able to detect gluten in beer), but is likely to also fail to detect hydrolyzed gluten that remains in beer (false negative).

A 2023 study by Australian researchers illustrates this point by comparing ELISA and LC-MS results for nine supposedly "gluten free" or low gluten beers made from barley (one Australian, one German, two British, and five Finnish beers).[14] While the less accurate ELISA tests estimated gluten levels to be below 20 ppm for all of the surveyed low gluten beers (as well as some of the non-hydrolyzed control beers), the LC-MS results indicated "several [low gluten] beers contained net hordein content comparable to high-gluten control beers. Notably, several intact immunogenic epitopes were seen in [low gluten] beers at levels comparable to control beers, and five [low gluten] beers contained multiple peptides specific to the wheat proteome, indicating contamination had occurred and highlighting a unique risk for CD food safety regulation."[14]

Given the fundamental challenges of reliably reducing gluten in beer for those with a medical reason to avoid it, and in light of improved alternative grain malting and brewing methods, the best practice for making gluten free beer is, simply put, using naturally gluten free ingredients.

Legislation on Labeling By Country


Gluten free standards and labeling requirements are regulated by the Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT, in English: National Administration of Drugs, Foods and Medical Devices), and addressed specifically in the Código Alimentario Argentino (Argentine Food Code), article 1383. Gluten free food products must be made only with foods naturally free of gluten containing grains (including barley, wheat, rye and oats) and must be able to demonstrate they are free from cross contact with gluten (measured as less than 10 ppm -- hence more stringent than the European standard). Gluten Free products must display the "SIN T.A.C.C." logo ("sin trigo, avena, cebada, centeno", i.e. without wheat, oats, barley, rye).[15] Under these guidelines Argentine law does not permit any gluten- free, "reduced", "removed", or "low gluten" designations on beers made with gluten containing grains that have been treated with a PEP enzyme. This was demonstrated in a 2019 recall of a gluten reduced beer that carried a "gluten free" label claim.[16][17]

Australia and New Zealand

Food Standards Australia and New Zealand (FSANZ) is the bi-national body that develops and administers food standards in the two countries. Gluten free protections for consumers are some of the most robust world wide. Gluten free claims can only be made for products with no detectable gluten (versus UK and EU provisions for <20ppm levels).[18] Like the US and Canada, gluten free beer can only be made with naturally gluten free grains, but unlike their North American counterparts, Australia and New Zealand do not permit oats in products that make a gluten free claim. Beers made from barley and treated with with a PEP enzyme to hydrolyze gluten proteins may be sold as "Low Gluten" provided they test below 200ppm by ELISA methodology, but "creative terms such as ‘no added gluten’, ‘gluten friendly’, ‘gluten removed’, ‘coeliac friendly’ or ‘99% gluten free’ are not permitted under the Code."[18] Coeliac Australia emphasizes low gluten beers are not suitable for people with coeliac disease.


Labeling rules for gluten free claims on beer are regulated by the federal government under section B.24.018 of the Food and Drug Regulations and enforced by the Canadian Food Inspection Agency (CFIA). Per the CFIA's statement on gluten-free claims, beer made from gluten containing grains (barley, wheat, rye, triticale) cannot make a claim of being gluten free: "Although additional processing steps in the beer making process can be taken to remove gluten, results from currently available analytical testing methods for gluten, including ELISA tests, are not sufficient to substantiate a "gluten-free" claim on these products." (emphasis added). Products that employ a PEP enzyme may label these beers as "processed or treated or crafted" to remove gluten with the caveat: "The gluten content of this product cannot be verified, and this product may contain gluten". Claims around gluten reduction must be substantiated with details of the process and evidence of lab testing.

Beers made exclusively from non-gluten containing grains conversely are allowed to be labeled "gluten free", with the following stipulation: "Health Canada and the CFIA do not object to the use of a "gluten-free" claim on a beer-like product derived from a non-gluten grain if it meets the requirements outlined for 'gluten-free' claims. This includes ensuring that all ingredients used in the manufacture of the product are gluten-free and that there is no cross-contamination with gluten containing ingredients during processing."[19]

Questions and complaints regarding beer labeling or advertising that contravene these rules can be made via online form with the CFIA.

In 2019, amendments to Canadian Food and Drug Regulations were introduced to remove previous exemptions on listing ingredients on beer. Going forward, beer -- whether made from gluten or non-gluten containing ingredients -- must indicate ingredients and possible gluten and allergen sources. Labeling to meet the new regulations must be in place by December 14, 2022.

United Kingdom and Europe

A key reference for food labeling in Europe and in post-Brexit United Kingdom is the World Health Organization's Codex Alimentarius.[20] According to the UK Department for Environment, Food & Rural Affairs, "The Codex international standards are voluntary good practice and not legally binding. They aim to ensure the safety, quality and fairness in international food trade and protect consumers. UK foods standards generally go above and beyond the Codex standards."[21]

Standard for Foods for Special Dietary Use For Persons Intolerant to Gluten (CXS 118-1979) is a standard adopted within the Codex in 1979 (and since amended in 2015) pertaining more specifically to gluten free foods and the often-referenced threshold level of 20 mg/kg (aka 20 ppm) of gluten protein levels.[22] The 118-1979 standard identifies Enzyme-linked Immunoassay (ELISA) as a method for determining gluten content in foods. In 2014 the European Union implemented Regulation 828/2014 "on the requirements for the provision of information to consumers on the absence or reduced presence of gluten in food".[23] The objective of the regulation is to harmonize "rules on the information provided to consumers on the absence (‘gluten-free’) or reduced presence of gluten (‘very low gluten’) in food. The rules of that Regulation are based on scientific data and guarantee that consumers are not misled or confused by information provided on a divergent basis on the absence or reduced presence of gluten in food."[23]

The EU regulation notes that "The removal of gluten from gluten-containing grains presents considerable technical difficulties and economic constraints and therefore the manufacture of totally gluten-free food when using such grains is difficult." And furthermore, "In order to enable individuals to find on the market a variety of foodstuffs appropriate for their needs and for their level of sensitivity, a choice of products should be possible with different low levels of gluten within such a restricted range. It is important, however, that the different products are properly labelled in order to ensure their correct use by people intolerant to gluten with the support of information campaigns fostered in the Member States." (emphasis added).[23]

In spite of recognizing these concerns (i.e. the difficulty of removing gluten from gluten-containing grain and the need for proper labeling and education), EU and UK legislation currently fails to adequately protect coeliac and gluten intolerant consumers. Though barley must be identified in the list of ingredients, there is no clear or obvious distinction made between barley-based beers and ones made from 100% non gluten containing ingredients (NGCI). Though the scientific community has highlighted barriers to accurately measuring gluten via ELISA testing in fermented and hydrolyzed foods, EU and UK labeling continues to rely on the false premise that beers tested 20ppm or below meet the gluten free claim. Because it is less costly to perform this test on PEP-treated barley-based beer than it is to brew naturally gluten free beer -- and because there is no legally mandated labeling incentive to do so -- the vast majority of "gluten free" beers made in these countries would fail to meet the standards set out in Australia, Canada, New Zealand and the United States. With these obstacles, only a very short list of breweries in the UK and Europe have currently adopted the naturally gluten free brewing best practice.

United States

Beer labeling in the United States is regulated by Alcohol and Tobacco Tax and Trade Bureau (TTB) with guidance from US Food and Drug Administration (FDA) regulations. Since 2013, FDA regulations have prevented gluten reduced beer products from using a gluten free claim. Gluten free beer must be made from naturally gluten free ingredients, or demonstrate that a gluten reduced product measures less than 20ppm using "a scientifically valid method that can reliably detect the presence of 20 ppm gluten in a variety of food matrices. For fermented or hydrolyzed foods (or foods containing fermented or hydrolyzed ingredients), however, FDA found that there is currently no scientifically valid analytical method available that can both reliably detect and accurately quantify the equivalent of 20 ppm intact gluten."[24] In 2015, the FDA set out to establish requirements for that testing in fermented and hydrolyzed products, but in its final October 2020 ruling, reiterated "that it knew of no scientifically valid analytical method effective in detecting and quantifying with precision the gluten protein content in fermented or hydrolyzed foods in terms of equivalent amounts of intact gluten proteins."[24] In short, gluten free beer sold in the US can only be made with naturally gluten free ingredients. Beers using a “[Processed or Treated or Crafted] to remove gluten” claim must provide details on the method used to ostensibly reduce the gluten level below 20ppm, but given there is no "scientifically valid assays that can accurately quantify the gluten content of fermented products", that evidence is used only to determine the direction and magnitude of that change, not to quantify the actual residual gluten content.[24]

Potential role of celiac (coeliac) associations

Celiac associations and gluten free beer advocacy - Social media graphic

Individuals with celiac disease are commonly represented by national associations, with organizations across North and South America, Australia and New Zealand, the United Kingdom, Europe, the Middle East and parts of Asia. These associations and societies typically provide guidance and support for newly diagnosed individuals and can play important education and advocacy roles, not just within the celiac community, but in consultation with government, healthcare, medical research, agriculture, food manufacturing, and hospitality sectors. Funding for these associations frequently comes from members and private donors, with limited government funding.

In the context of beer, celiac associations can advocate on multiple fronts:

  • Formally recognize naturally gluten free brewing as the best practice for ensuring the health and well being of celiacs and gluten intolerant individuals
  • Ensure beer labeling is accurate and transparent. Lobby government where there are gaps.
  • Stay abreast of and communicate research about the safety of gluten "reduced" beers, including barriers to accurate testing in fermented and hydrolyzed products.
  • Engage brewers interested in serving celiac populations and ensuring health standards through gluten free brewing best practices (i.e. using naturally gluten free ingredients).
  • Promote the growth of the naturally gluten free brewing industry, recognizing and spotlighting the importance of gluten free grain growers and importers, maltsters, brewers, distributors and retailers.
  • Be prepared to call for dramatic change in light of new evidence and international brewing practices -- placing the health and wellbeing of members ahead of conventional brewery sponsorship revenue

Celiac associations and support groups have provided guidance regarding beer and the safety of naturally gluten free versus gluten reduced beer. Perhaps not coincidentally, guidance from celiac groups to avoid gluten reduced beer is most clear in countries where there are better consumer protections for celiac beer consumers (in the form of labeling to distinguish gluten free from gluten reduced, for instance).

Organizations with clear recommendations to avoid gluten reduced beer:

  • Gluten.Org (US)[25], Beyond Celiac (US)[26], Celiac Canada[27], Coeliac Australia[28], Coeliac New Zealand[29]

Coeliac UK and the Association of European Coeliac Societies (AOECS)

Coeliac UK and European coeliac societies have taken a weaker and ultimately problematic stance on gluten reduced beer. On their website, Coeliac UK provides an overview of both naturally gluten free and gluten reduced methods (questionably noting from the top that naturally gluten free beers "often have slightly different aromas and flavours to regular beer.")[30] The FAQ indicates there are "pros and cons" with all testing methods but states that the R5 Competitive ELISA method is considered current state of the art and best validated. A Coeliac UK article that delves further into the topic acknowledges the US FDA's 2020 ruling that this method "is not suitable for the detection and quantification of gluten in fermented or hydrolysed foods or ingredients" and that this sets the UK and Europe apart from the US (along with other countries that do not recognize gluten reduced beer as gluten free).[31] Coeliac UK's stance seems to be positioned as providing informed consumer choice, though it's not clear how this aligns with labeling that puts barley-based PEP-treated beers on equal footing with those made only from gluten free ingredients. A summary of work in the area begins with a call to the brewing industry and scientific community to advance "the knowledge on the testing of gluten in hydrolysed and fermented products" (i.e. continued focus on barley-based beer). Notably absent in that action list is any work to help grow the NGCI beer segment.[31].

In a 2019 response to an open letter from a Finnish coeliac beer consumer, the AOECS points to the potential legal liability of changing the European definition of gluten free beer after establishing a 20ppm definition previously (for beers made with gluten containing grains).[32] The Director of the AOECS noted that there are inconsistent results from ELISA testing and that a European study commissioned to try to harmonize ELISA testing results "suggests that the current measurement system for gluten quantification cannot fully support the gluten-free claims as defined by legislative requirements, with a probability of 50% that a food that is deemed compliant with the 20ppm level might in reality contain 80-90ppm."[32] Curiously, this seems to have led the AOECS to an inverse position from North American, Australian and Argentinian counterparts: allowing the gluten free claim to stand for gluten reduced beers while uncertainty (not to mention lack of accuracy and reliability) remains with current testing methods. It appears that in Europe and the UK, for now, fear of legal backlash for changing labeling rules has won out over potential health considerations.

Peer Reviewed Articles

  • Nye-Wood, M.G.; Byrne, K.; Stockwell, S.; Juhász, A.; Bose, U.; Colgrave, M.L. (2023) Low Gluten Beers Contain Variable Gluten and Immunogenic Epitope Content. Foods 2023, 12, 3252.
  • Tanner GJ, Colgrave ML, Blundell MJ, Goswami HP, Howitt CA (2013) Measuring Hordein (Gluten) in Beer – A Comparison of ELISA and Mass Spectrometry. PLoS ONE 8(2): e56452.
  • Gregory J. Tanner, Michelle L. Colgrave & Crispin A. Howitt (2014) Gluten, Celiac Disease, and Gluten Intolerance and the Impact of Gluten Minimization Treatments with Prolylendopeptidase on the Measurement of Gluten in Beer, Journal of the American Society of Brewing Chemists, 72:1, 36-50,
  • Michelle L. Colgrave, Hareshwar Goswami, Malcolm Blundell, Crispin A. Howitt, Gregory J. Tanner (2014) Using mass spectrometry to detect hydrolysed gluten in beer that is responsible for false negatives by ELISA, Journal of Chromatography A, Volume 1370, Pages 105-114,
  • Laura K Allred, Katherine Lesko, Diane McKiernan, Cynthia Kupper, Stefano Guandalini (2017) The Celiac Patient Antibody Response to Conventional and Gluten-Removed Beer, Journal of AOAC INTERNATIONAL, Volume 100, Issue 2, Pages 485–491,
  • Michelle L. Colgrave, Keren Byrne, and Crispin A. Howitt (2017) Liquid Chromatography–Mass Spectrometry Analysis Reveals Hydrolyzed Gluten in Beers Crafted To Remove Gluten, Journal of Agricultural and Food Chemistry 65 (44), 9715-9725,
  • Malgorzata Rzychon, Marcel Brohée, Fernando Cordeiro, Reka Haraszi, Franz Ulberth, Gavin O'Connor (2017) The feasibility of harmonizing gluten ELISA measurements, Food Chemistry, Volume 234, Pages 144-154, ISSN 0308-8146,
  • Panda Rakhi, Garber Eric A. E. (2019) Detection and Quantitation of Gluten in Fermented-Hydrolyzed Foods by Antibody-Based Methods: Challenges, Progress, and a Potential Path Forward, Frontiers in Nutrition, 6,

See Also


  1. CSIRO webpage for Kebari
  2. Gluten-free barley: Lab to supermarket. Master Brewers Podcast, episode 112, Master Brewers Association of America
  3. Creation of the first ultra-low gluten barley (Hordeum vulgare L.) for coeliac and gluten-intolerant populations, Tanner et al (2015)
  4. Colgrave et al, Liquid Chromatography–Mass Spectrometry Analysis Reveals Hydrolyzed Gluten in Beers Crafted To Remove Gluten (2017)
  5. Panda and Garber, Detection and Quantitation of Gluten in Fermented-Hydrolyzed Foods by Antibody-Based Methods: Challenges, Progress, and a Potential Path Forward (2019)
  6. 6.0 6.1 The Brü Lab podcast Episode 014: The Celiac Response To Gluten In Beer with Dr. Laura Allred, Gluten Intolerance Group
  7. Segura et al, A Highly Sensitive Method for the Detection of Hydrolyzed Gluten in Beer Samples Using LFIA (2022)
  8. Fasano A (Jan 2011). "Zonulin and its regulation of intestinal barrier function: the biological door to inflammation, autoimmunity, and cancer". Physiol. Rev. (Review)
  9. Immune Epitope Database and Analysis Resource
  10. Food and Drug Administration, Food Labeling; Gluten-Free Labeling of Fermented or Hydrolyzed Foods, August 13, 2020
  11. Measuring Hordein (Gluten) in Beer – A Comparison of ELISA and Mass Spectrometry
  12. Celiac Patient Antibody Response to Conventional and Gluten Reduced Beer
  13. R-Biopharm, Gluten analysis of fermented or hydrolyzed food products (2020)
  14. 14.0 14.1 Nye-Wood, M.G.; Byrne, K.; Stockwell, S.; Juhász, A.; Bose, U.; Colgrave, M.L. Low Gluten Beers Contain Variable Gluten and Immunogenic Epitope Content. Foods 2023, 12, 3252.
  16. Retiro preventivo del mercado nacional del producto Cerveza Rubia Premium – Blonder Ale, Argentina Ministry of Health, ANMAT, October 18, 2019
  17. Asociación Celíaca Argentina, Facebook Post, October 21, 2019
  18. 18.0 18.1 Coeliac Australia: Making a Gluten Free Claim
  19. CFIA statement on gluten free beer claims (retrieved August 10, 2020)
  20. Codex Alimentarius, Food and Agriculture Organization of the United Nations
  21. UK Government, Food standards: labelling and composition (retrieved August 22, 2022)
  22. CXS 118-1979
  23. 23.0 23.1 23.2 European Union Commission Implementing Regulation (EU) No 828/2014 on the requirements for the provision of information to consumers on the absence or reduced presence of gluten in food
  24. 24.0 24.1 24.2 TTB Ruling, Gluten Content Statements in the Labeling and Advertising of Wine, Distilled Spirits, and Malt Beverages, October 13, 2020
  25. Gluten.Org: Does Fermentation or Distillation Make a Product Gluten Free?
  26. Beyond Celiac: Gluten Free Beer
  27. Celiac Canada on Alochol and Alcohol labeling
  28. Coeliac Australia, Making a GF Claim
  29. Coeliac New Zealand: What Alcohol Can I Drink
  30. Coeliac UK, FAQ: How is gluten free beer made
  31. 31.0 31.1 Coeliac UK, Emerging evidence on tests for analysing gluten
  32. 32.0 32.1 Blog post: "Safety of Gluten Free Beer: AOECS response to my open letter", (2019)