Extraction of oil from ground corn using ethanol
Abstract
Abstract Corn oil was extracted from whole ground corn using ethanol as the solvent. The yield of oil was measured as a function of temperature, time of extraction, solvent‐to‐solids ratio, and ethanol concentration. Optimal conditions were a solvent‐to‐solids ratio of 4 mL/g corn, an ethanol concentration of 100%, 30 min of extraction time, and a temperature of 50°C. Under these conditions, a single batch extraction yielded ≈3.3 g oil/100 g corn, equivalent to 70% extraction efficiency. A three‐stage extraction, where the same corn was exposed to fresh ethanol, resulted in a yield of ≈4.5 g/100 g corn (2.5 lb/bu of corn), equivalent to 93% recovery of the oil in corn. When anhydrous ethanol was used to repeatedly extract fresh corn, moisture was absorbed linearly by ethanol from the corn in successive stages, which, in turn, decreased oil yield and increased nonoil components in the extract.