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
Bread mainly found in hulls in the form of insoluble bound ferulic acid, where it is relevant to wheat resistance to fungal diseases. Rye bread contains phenolic acids and ferulic acid dehydrodimers. Three natural phenolic glucosides, secoisolariciresinol diglucoside, p-coumaric acid glucoside and ferulic acid glucoside, can be found in commercial breads containing flaxseed. Glutenin and gliadin are functional proteins found in wheat bread that contribute to the structure of bread. Glutenin forms interconnected gluten networks within bread through interchain disulfide bonds. Gliadin binds weakly to the gluten network established by glutenin via intrachain disulfide bonds. Structurally, bread can be defined as