Effect of a new developed extruding-expanding pre-treatment technique on soybean oil and meal protein qualities

A new extruding-expanding pre-treatment technique was developed which decreased procedure comparing with the traditional extruding-expanding processing. The new technique has advantages in the extraction rate of oil and energy demand, by which soybean only needs cleaning, crashing, extruding-expanding and extracting. Soybean oil and meal produced by the new technique were believed to have unique characteristics. Results show that the peroxide value (POV) of the crude oil produced by traditional processing is 72.76 meq/kg, evidently higher than that by the new technique which was 9.80～32.51 meq/kg after storage in 60℃ for 30 days. The subsequent soybean meals protein produced by the new technique have a higher NSI value which increases 9.39%～35.92% in pH 7.0 comparing with the traditional processing.