Frequently Asked Questions

1. Food products are purchased from store shelves and through mail-order.

2. For each specific product tested, three samples (e.g., 3 packages of noodles, 3 boxes of cereal, 3 bags of chips) are purchased.

3. Samples are sent unopened to Bia Diagnostics, an independent food testing lab in Burlington, Vermont.

4. Samples are tested in duplicate using the standard sandwich R5 ELISA (R7001 Ridascreen Gliadin) and extracted with the cocktail solution (Art. No. R7006, official R5 Mendez method). If needed, samples also may be tested using the competitive R5 ELISA (R7011 Ridascreen Gliadin Competitive).

At the present time the R5 ELISA (R7001 Ridascreen Gliadin) is widely regarded as the best available validated ELISA for assessing final food product for gluten. The R5 ELISA is one of only two commercially available ELISAs validated at the levels used for regulatory purposes and official governmental methods (the other is the Morinaga Wheat Protein ELISA). The R5 ELISA is included in the FDA’s proposed gluten-free labeling rule as a possible method for rule enforcement.

Testing three samples instead of one gives us a better "picture" of the gluten content of the product. Regardless, this is a snapshot of the gluten content of a particular product at one point in time. There is no way of knowing without testing many more samples whether the results of the three samples tested are representative of the gluten content of this product as a whole.

Testing each sample in duplicate does two things: it helps guard against laboratory error and it helps ensure that the sample tested is homogenized. This means that any contaminant (in this case gluten) is well distributed within the sample. If the results of the two extractions are fairly similar a reasonable amount of confidence can be placed in the results. Some products may be more difficult to homogenize than others. It is the policy of Gluten Free Watchdog to not report extraction values from samples where gluten contamination remains highly heterogeneous even after rigorous mixing.

We will test at least four new products monthly. This program is subscriber/sponsor driven. The more subscribers we have the more products we can analyze for gluten.

Gluten Free Watchdog, LLC will conduct follow-up testing of products that test greater than or equal to 20 parts per million of gluten within one year of the original test date.

Any product labeled gluten free may be selected for testing. Products are randomly selected from store shelves and also may be mail ordered. Consumers and dietitians also may request testing of a certain product via our contact form. A request for testing does not automatically mean that a product will be tested.

No. All products tested are purchased by Gluten Free Watchdog, LLC at retail outlets.

It is the policy of Gluten Free Watchdog to file a report with the FDA Consumer Complaint Coordinator if a product continues to test high on follow-up testing.

When a food tested by Gluten Free Watchdog tests at or above 20 parts per million of gluten, the manufacturer is contacted and provided with the test results. It is hoped that by alerting manufacturers to potential problems they will take the steps necessary to resolve any issues that may be causing products to test high. This is why Gluten Free Watchdog retests products that test at or above 20 parts per million of gluten within one year of the original test date—it is hoped (actually expected) that at the time of retesting the product will test less than 20 parts per million of gluten.