When is Gluten Free not Free of Gluten?

If you, as I, thought that a product labeled as “Gluten Free” which contained cereal flours or starches, other than the usual suspects as wheat, barley, rye, was 100% free of gluten forming proteins consider this research paper: ,

3. Results

3.1. Proximate Composition of GF Flours

The gluten content (expressed in ppm) for the flours under investigation was as follows: 14.15 (rice), 8.63 (brown rice), 7.22 (maize), 6.14 (oat), 8.75 (millet), 8.42 (teff), 5.3 (amaranth), 3.94 (buckwheat), 8.04 (quinoa), 4.66 (chickpea), 2.02 (gram), 4.78 (tiger nut), and 3.68 (plantain).

 All the flours had a gluten content lower than 20 ppm, which confirms their claim as gluten-free.

https://www.mdpi.com/2076-3417/11/14/6283#

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