Sequential extraction processing: alternate technology for corn wet milling

Abstract

A laboiatoiy extractor-simulator was developed to demonstrate the feasibility of extracting oil from undegermed com, the first step in sequential extraction processing. The effects of flaking and grinding, com variety, and extracting solvent, concentration and temperature on oil recovery were assessed. Protein loss during oil extraction was also evaluated. Flaked com showed better extraction characteristics than ground conu Oil recovery was higher in varieties having substantial amounts of floury endosperm (soft dent and high-lysine com). Ethanol, isopropanol, acetone, butanol, and the butanol:acetone:ethanol mixture (6:3:1) all showed oil recoveries which were either equal to or better than the 72% obtained by conventional prepress hexane extraction methods in industry. Greater oil recoveries were achieved using anhydrous concentrations and temperatures close to the boiling point of the solvent. Low temperature extraction, however, appears feasible when using butanol:acetone:ethanol, ethanol, and isopropanol Butanol, isopropanol and ethanol reduced the total crude protein content of the flaked com, particularly when high aqueous concentrations and high temperatures were used for oil extraction.

Solvent Extraction of Zein from Dry‐Milled Corn

“…Mossé (1961) also reported similar behavior with corn endosperm. Hojilla- Evangelista (1990) found that 55°C was the optimum temperature for extraction, and temperatures >65°C resulted in protein denaturation.…”