Barley straw lignin

In many of the intensive rice-growing areas of the world, particularly Asia, this straw is used as a food for farm animals. Its protein content and metabolisable energy value are similar to those of spring barley straw. It has an exceptionally high ash content, about 170 g/kg DM, which consists mainly of silica. The lignin content of this straw, about 60-70 g/kg DM is, however, lower than that of other cereal straws. In contrast to other straws, the stems are more digestible than the leaves. 

Sun, R.-C., et al. "Fractional and Structural Characterization of Lignins Isolated by Alkali and Alkaline Peroxide from Barley Straw." Journal of Agricultural and Food Chemistry 49 (2001), 5322-5330. 

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