Secalin is a protein found in the grain rye

Rye

Rye is a grass grown extensively as a grain and as a forage crop. It is a member of the wheat tribe and is closely related to barley and wheat. Rye grain is used for flour, rye bread, rye beer, some whiskeys, some vodkas, and animal fodder...

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Secalin is one of the forms of gluten

Gluten

Gluten is a protein composite found in foods processed from wheat and related grain species, including barley and rye...

 that people with coeliac disease

Coeliac disease

Coeliac disease , is an autoimmune disorder of the small intestine that occurs in genetically predisposed people of all ages from middle infancy onward...

 cannot tolerate, and thus rye should be avoided by people with this disease. It is generally recommended that such people follow a gluten free diet.

In bread making with rye flour, this protein requires exposure to an acid such as lactic acid

Lactic acid

Lactic acid, also known as milk acid, is a chemical compound that plays a role in various biochemical processes and was first isolated in 1780 by the Swedish chemist Carl Wilhelm Scheele. Lactic acid is a carboxylic acid with the chemical formula C3H6O3...

 so that the bread will rise. This is usually achieved with a sourdough

Sourdough

Sourdough is a dough containing a Lactobacillus culture, usually in symbiotic combination with yeasts. It is one of two principal means of biological leavening in bread baking, along with the use of cultivated forms of yeast . It is of particular importance in baking rye-based breads, where yeast...

 ferment

Fermentation (food)

Fermentation in food processing typically is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids using yeasts, bacteria, or a combination thereof, under anaerobic conditions. Fermentation in simple terms is the chemical conversion of sugars into ethanol...

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