Testing for Gluten Contamination

What we’ve learned from 15 years of testing food for gluten & 8 years running Gluten Free Watchdog

The vast majority of
manufacturers of gluten-free foods are doing it right!

87% of labeled gluten-free foods commissioned for testing through Gluten Free Watchdog test below 5 parts per million of gluten (the lowest level that can be quantified using the R5 ELISA Mendez Method).

96% of labeled gluten-free foods commissioned for
testing through Gluten Free Watchdog test below 20 parts per million of

4% of labeled gluten-free foods commissioned for
testing through Gluten Free Watchdog test at or above 20 parts per […]

Morning musings about testing food for gluten & the Nima Sensor

The following is paragraph form of a tweet thread posted by @GFWatchdog to Twitter on March 21, 2019.

A few musings this morning about testing food for gluten & the Nima Sensor. Background, I have been commissioning testing of gluten-free food for about 15 years. Does this make me an expert? No. I am a dietitian fortunate to have learned from the experts—the scientists who specialize in testing food for gluten, including the late Dr. Mendez (you may recognize his […]

Adrian Rogers from Romer Labs presents: Gluten analysis and the challenges of consumer testing devices

June 28, 2018

Adrian generously agreed to allow us to post his slides from yesterday’s Medical Nutrition Practice Group webinar, Gluten analysis and the challenges of consumer testing devices. In this webinar Adrian provides information on:

Gluten Analysis: The challenges
Current Methods of Analysis
Consumer testing devices: Pros and Cons
Gluten Detective : Opinion

If a link to the audio becomes available, it will be posted.

Update: Here is the link to the audio and slides https://eatright.webex.com/eatright/ldr.php?RCID=febe8b09e673ea25bc4505779f32450f 

If you have any questions for […]

Gluten-Free Quaker Oats & Testing with the Nima Sensor, R5 ELISA, & G12 ELISA

November 6, 2017

Please read this entire document very carefully. The information is presented in bullet point format to hopefully make complicated information a bit easier to understand.


A consumer tested a carton of Quaker Oats labeled gluten-free with the Nima Sensor consumer-testing device. Two samples—one cooked and one raw were tested. Both results were “gluten found”.
The consumer sent all remaining product in the original container to Gluten Free Watchdog.
Gluten Free Watchdog sent the product to an […]

Article Summary: Gluten-Free Labeling: Are Growth Media Containing Wheat, Barley, and Rye Falling through the Cracks?

Article Summary:
Gluten-Free Labeling: Are Growth Media Containing Wheat, Barley, and Rye Falling through the Cracks?
Tricia Thompson, Melinda Dennis, Luke Emerson. J Acad Nutr Dietet. 2017. In Press. 
Background: Bacteria are used in a variety of products, including probiotics. These microorganisms may be grown on media that may include ingredients derived from gluten-containing grain (ie, wheat, barley, and rye). Historically, some concern has been expressed in the celiac disease community that the use of gluten-derived/ gluten-containing growth media may result […]

Fermentation Growth Media for Yeast and Concerns about Residual Gluten

Gluten Free Watchdog recently received a question about the yeast used in a Crispin (Miller-Coors) hard cider certified gluten-free by GFCO. Neither GFCO nor Miller-Coors would disclose the growth medium used for the yeast.

Yeast testing: In an attempt to learn more about residual gluten protein in yeast grown on gluten-containing growth media Gluten Free Watchdog tested White Labs Pilsner Yeast cultured in a solution containing barley malt for gluten. This yeast is NOT labeled gluten-free. But, according to the […]

Lateral Flow Devices (Nima, Gluten Tox Home, EZ Gluten) to test food for gluten: Manufacturer & Consumer Use

This article was originally published in 2012 on glutenfreedietitian.com. Due to the marketing of the new consumer lateral flow device (LFD) NIMA there is a renewed interest in LFDs. An updated version of the article is republished here. If you are a manufacturer or consumer who currently uses or is thinking of using a LFD please take the time to read this article.

 Thank you to Thomas Grace of Bia Diagnostics, www.biadiagnostics.com and Adrian Rogers of Romer Labs https://www.romerlabs.com/ for sharing their […]

Using Nima to test mustard for gluten contamination

The video is embedded below. First a recap of Nima testing to date …

Sampling methodology for Nima: Gluten Free Watchdog has been assessing Nima’s sampling methodology. Users are advised to place a small sample of food inside a disposable capsule. A small sample is defined as “pea sized.”

In the opinion of Gluten Free Watchdog, this sampling method is not well suited for testing packaged foods that may have heterogeneous (unevenly distributed) gluten contamination or restaurant meals with spotty cross […]

Mystery Grain in Edison Grainery Lentils Tests “Low Gluten” Using Nima

This post is an update to the blog posted on December 13th entitled “General Product Warning: Check Your Lentils (including certified gluten-free lentils) for Foreign Grain” available at https://www.glutenfreewatchdog.org/news/general-product-warning-check-your-lentils-including-certified-gluten-free-lentils-for-foreign-grain/

Long story short: A consumer found a single errant grain in each of two bags of Edison Grainery certified gluten-free lentils. Photos of the grain were sent to Edison Grainery. The consumer was advised that the grain was likely wild oat, oat, or rice. Gluten Free Watchdog sent one of the […]