The production of bio-based ethanol has been one of the fastest growing industries in the U.S. during the last decade. The generated co-products are currently fed to livestock. Whole stillage, thin stillage, and condensed distillers syrup are the major upstream materials used to produce coproduct feeds. The storability of whole stillage, thin stillage and syrup influences the economic and energetic balances of fuel ethanol production. But there are few investigations of the shelf life for those products, or how to measure these quantities. The objectives of this research were to test physical and chemical properties of whole stillage, thin stillage, and syrup, and determine storability and allowable shelf life for these materials as influenced by storage temperature levels. Using standard laboratory methods, several properties were determined, including moisture content, water activity, thermal properties (conductivity, resistivity, volumetric heat capacity, and diffusivity), color, crude protein, crude fat, crude fiber and CO₂ production.