Rye rye harvesting was a manual task performed with scythes or sickles. The cut rye was often shocked for drying or storage, and the threshing was done by manually beating the seed heads against a floor or other object. Like wheat, barley, and their hybrids and derivatives, rye contains gluten, which makes it an unsuitable grain for consumption by people with gluten-related disorders, such as celiac disease, non-celiac gluten sensitivity, and wheat allergy, among others. Nevertheless, some wheat allergy patients can tolerate rye or barley. Ergotism is an illness that can result from eating rye and other grains infected by ergot
Rye bread "Lactobacillus" "sourdough" cultures lowers bread pH, facilitating growth of an acid-tolerant yeast strain, and helping gelatinize starches in the dough matrix. The byproduct of this approach is lighter breads. In areas where high-gluten hard wheat is readily available the need for a complex polyculture of bacteria and yeast can often be reduced or removed by adding a large proportion of hard wheat flour to the rye flour. Its added gluten compensates for amylase activity on the starch in the dough, allowing the bread to retain its structure as it bakes. The "deli rye" tradition in the United States is based