PARTICLE SIZE DISTRIBUTIONS OF GROUND CORN AND DDGS FROM DRY GRIND PROCESSING

摘要

Ethanol production has increased in the past decade as a result of growth in the dry grind industry. In the dry grind process, the first step is grinding of corn. The particle size of the resulting ground com can affect the fermentation process and the particle size of dried distillers' grains with solubles (DDGS), a coproduct of dry grind processing. Few data are available that characterize particle size distributions of ground corn or DDGS. The objective was to determine particle size distributions of ground com and DDGS. Samples of ground corn and DDGS were obtained from nine dry grind plants; particle size distribution, geometric mean diameter (d{sub}(gw)) and geometric standard deviation (S{sub}(gw)) were determined. The d{sub}(gw) of ground corn and of DDGS were not different among processing plants. The overall mean d{sub}(gw) of ground com was not different from that of DDGS. Most of the ground corn (80 g/100 g) and DDGS (70 g/100 g) were recovered in the three largest particle size categories. The particle size distributions of ground corn were not correlated (r < 0.35) to particle size distributions of DDGS.