Rye (Secale cereale) is a hardy kind of cereal grass that can survive in tough climates. It can grow at cold, even sub-zero, temperatures, in slightly acidic soil, and at high altitudes. Because of this rye is typically grown in areas where other grains cannot survive. Rye crops are much taller than wheat crops, growing as high as a person's head. The rye grain is also darker than the wheat kernel.
Rye was originally a weed found in grain fields in Asia Minor. Because it was such a hardy crop it became widely grown in the harsh regions of Eastern Europe and Russia, where it was referred to as peasant's "black wheat". Rye was also a major crop of the Vikings. Farmers would often plant both wheat and rye in the same field. Depending on the weather conditions that year one of the two would mainly grow. The mixture crop that was produced would yield a unique kind of flour called “maslin flour”. Besides Eastern Europe, rye is also commonly grown in Canada, China, Germany and the Scandinavian areas.
Rye is more nutritious than wheat, generally having higher levels of protein and fiber. It is also a good source of thiamine, iron, phosphorous, and potassium.
Whole rye kernels are ground to produce rye flour. The resulting flour is heavier than wheat flour and contains less gluten. This means that bread produced from rye flour will be denser than wheat breads. Bakers use a combination of rye and wheat flour to create a lighter bread loaf. Bread made from rye flour is also browner in color than wheat loaves because the rye flour itself is darker than wheat flour. Rye flour is naturally a grayish-tan color, so bread makers often add caramel coloring or molasses to make rye breads browner. Rye flour has a very distinctive sweet-sour earthy flavor. Vinegar may be added to rye bread dough to help bring out the rye flavors. Rye flour also may be added to sourdough bread to give the loaf additional flavors. The flour should be used quickly or stored in the refrigerator or freezer to prevent the oils in the flour from becoming rancid.
There are four different types of rye flour: light, medium, dark, or pumpernickel. These types vary depending on how the rye is milled. Lighter rye flours have more of the bran removed during milling. This means that the lighter flours have less protein and fiber and a milder taste than darker flours. Medium rye flour is the most common type of rye flour made. Pumpernickel flour is the darkest, coarsest rye flour. It is ground from the entire rye kernel, much like whole wheat flour is ground from the entire wheat kernel.
Whole rye kernels can be cooked and eaten much like wheat berries. Rye kernels, along with corn and barley, can also be fermented and made into rye whiskey.
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