ANALYSIS OF THE OIL EXTRACTION PROCESS IN SOYBEANS: A NEW CONTINUOUS PROCEDURE.

Soybean oil extraction techniques were studied in which solvent was recirculated or pumped once through a suspension of soybean tissue. Both refractive index and ultraviolet absorbance were used to monitor the extraction continuously. Slices of soybean tissue showed rapid extraction from damaged tissue, followed by slow extraction from intact tissue. When soybean flakes were extracted, a continuously decreasing rate was noted. When solvent was forced through flakes, extraction was more rapid than when solvent was allowed to diffuse in and out of flakes. Reextraction of partially defatted flakes showed that the last soybean oil to be extracted was not inherently resistant to extraction.