Dorchester Brewing Company · Boston, MA
Test Sour
Is Test Sour gluten free?
No. Test Sour by Dorchester Brewing Company is gluten-reduced, not gluten-free. It is brewed from gluten-containing grain and treated with the Clarity Ferm enzyme, which breaks gluten proteins into fragments. Reported testing: <10 ppm. Under US TTB rules a beer brewed from barley cannot be labelled gluten-free, and enzyme-reduced beer is not considered safe for people with celiac disease.
- Category
- Gluten-reduced (enzyme-treated)
- Verification
- Brewery confirmed
- Style
- Sour Ale
- ABV
- Not published
- Enzyme
- Clarity Ferm
- Reported gluten
- <10 ppm
- Test method
- Not published
- Last verified
- 2026-07-16
- Whole lineup treated?
- No
- Distribution
- Not published
Research notes
Collab with Stillwater Artisanal; 'an enzyme that specifically breaks down proline rich gluten forming proteins'; '< 10 parts per million'
Where to buy
No retail partners have listed this beer yet. Try the brewery's own site (linked above), or a local liquor store's search.
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Questions people ask
Is Test Sour gluten free?
No. Test Sour by Dorchester Brewing Company is gluten-reduced, not gluten-free. It is brewed from gluten-containing grain and treated with the Clarity Ferm enzyme, which breaks gluten proteins into fragments. Reported testing: <10 ppm. Under US TTB rules a beer brewed from barley cannot be labelled gluten-free, and enzyme-reduced beer is not considered safe for people with celiac disease.
Can I drink Test Sour if I have celiac disease?
No. Test Sour is gluten-reduced, not gluten-free, and enzyme-treated beer is not considered safe for people with celiac disease. Even trace and fragmented gluten can trigger an immune response. Choose a beer brewed from naturally gluten-free grains instead, and speak to your doctor.
What enzyme is used in Test Sour?
Dorchester Brewing Company uses Clarity Ferm, a brand of the AN-PEP (Aspergillus niger prolyl endopeptidase) enzyme. It is added during fermentation, where it cuts gluten proteins at proline sites. Brewers typically adopt it to prevent chill haze rather than to reduce gluten.
How much gluten is in Test Sour?
Reported testing for Test Sour: <10 ppm. Treat reported ppm as indicative rather than definitive — the standard R5 ELISA test can under-read the gluten fragments an enzyme produces.
Should I order Test Sour on draft?
Prefer a sealed bottle or can. Shared tap lines can carry residue from other beers poured through them, which can reintroduce gluten regardless of how the beer itself was brewed.
Gluten claims on this page are independently researched from published sources and community reports — they are not verified by lab testing by Off Label. Recipes and processes change without notice, and enzyme use can vary between batches; we cannot guarantee this beer is currently gluten-reduced. If you have celiac disease or severe gluten sensitivity, confirm directly with the brewery before consuming. Enzyme-reduced beer is not gluten-free. Nothing here is medical advice.