Distiller’s Dried Grain Solubles: A by-product of grain based distillery. In alcohol production, starch is fermented to obtain ethyl alcohol. The remaining components of the grain preserve much of the original nutritional value of the grain, including energy. protein, phosphorous. These nutritional components hove conventionally been incorporated into animal feed. The feed is further enriched with amino acids and vitamins produced by the use of yeast in the process.