Gluten-free beer example: Sheehan, Evans & Skerritt, 2001). Brewers who produce low gluten beers are required to test every batch for gluten, and record gluten levels in "parts per million" ('ppm'). Although the barley hordein in such tests may not be detected, smaller pieces of these proteins, known as peptides, may remain and be toxic for celiacs. Those involved in gluten-free brewing, and others representing celiacs or those with other conditions that require a gluten-free diet, tend to be concerned that beer brewed using wheat or barley are not appropriate for those with celiacs or dermatitis herpetiformis, although the carefully controlled gluten
Gluten-free diet food bearing the claim in its labelling may not contain: Any food product that inherently does not contain gluten may use a gluten-free label where any unavoidable presence of gluten in the food bearing the claim in its labelling is below 20 ppm gluten. Gluten-free diet A gluten-free diet (GFD) is a diet that strictly excludes gluten, a mixture of proteins found in wheat and related grains, including barley, rye, oat, and all their species and hybrids (such as spelt, kamut, and triticale). The inclusion of oats in a gluten-free diet remains controversial, and may depend on the oat cultivar