Studies on Extraction of Soybeans by Liquid Butane. III.

Quality of the Extraction Products

Abstract

The butane extraction products from newly harvested soybeans have a good quality. The conclusions drawn from comparative data on butane and hexane extractions of newly harvested soybeans are briefly summarized as follows.
1. Butane extraction oil is light-colored and has low acid value and lecithin content. The refined, bleached and deodorized oil has a good stability showing little reversion tendency of the color and flavor. The fatty acid composition of butane extraction oil is practically same with that of hexane extraction oil, indicating that neither extraction solvent nor extraction temperature affects the fatty acid composition of oil.
2. Lecithin from the butane extraction oil is light-colored.
3. Butane extraction meal contains soluble proteins in a proportion of about 9093% of the total proteins. Manufacturing Tofu (bean-curds) from butane extraction meal, they are obtained in a high yield and have a high score in a laboratory panel flavor test.
The extraction products from dehulled soybeans and the products obtained at a lower extraction temperature are generally superior in their quality to the products from non-dehulled soybeans and those obtained at a higher extraction temperature, respectively.
The superiority of the quality of butane extraction oil to that of hexane extraction oil is attributable to the preferential extraction of neutral glycerides in addition to the low extraction temperature in the case of butane extraction.