Sugar Beet Quality Improvement

More than one-third of the sugar (sucrose) consumed by humans is obtained from sugar beet (Beta vulgaris L.). Sucrose extraction begins with the production of a dark opaque juice from strips of sugar beet. This juice is purified with lime and carbon dioxide, thickened by evaporation, and crystallized under a vacuum. Soluble nonsucrose constituents of sugar beet, referred to collectively as impurities, impede sucrose crystallization in normal factory processes. Sucrose concentration and the ratio of sucrose to total soluble solids (sucrose plus impurities) determine processing quality of sugar beet. Among the more important impurity components are sodium, potassium, and amino-nitrogen. Sucrose and impurity concentrations can be altered in breeding programs. However, a negative association between root yield and sucrose concentration and interactions among impurity components and between impurity components and yield or sucrose concentration have complicated breeding efforts. Also, almost any cultural practice may affect the quality of the crop. Nitrogen fertilizer management is a challenge wherever sugar beet is grown. Producers' returns can be increased with proper nitrogen application but even moderate over-fertilization may result in a costly reduction in crop quality. Both producers and processors operate on small profit margins. In this economic environment, producing a high quality crop is a necessity.