"The grain of rye is darker in color than that of wheat, but is otherwise similar in appearance. Rye flour differs from wheat flour in flavor, the liking for the one or the other being a matter of preference. It differs, however, in another way and in an important particular—its gluten has not the same elastic, tenacious quality and does not yield so light and well-raised a loaf. Although this fact and its dark color make it less popular than wheat, it is second in importance as a breadstuff. It is more easily raised than wheat, especially in cold countries, and therefore has a lower market value. In many parts of Europe it practically replaces wheat among the poor and in army rations. When it is milled entire, as it usually is, it contains more protein than wheat flour, but is probably less completely digested. Wheat and rye flour are often used together in bread making."