/kloc-0 At the end of 909, the United States imported soybean oil for the first time. From1917-1921,a large amount of soybean oil imported from Northeast China is refined with refined cottonseed oil. The result was disappointing. Refined soybean oil has obvious "fishy smell" or "paint smell". Only when there is a serious shortage of oil in wartime can the food industry accept it. Because of this taste problem, soybean oil has a bad reputation compared with refined cottonseed oil, corn oil and peanut oil. In 1927, it is determined that the odor of soybean oil is mainly due to the existence of methyl n-nonone. 1928 refined and deodorized soybean oil according to the method of refining corn oil, and developed products with good flavor and light color. However, a few weeks later, the "reversal" occurred, and the refined soybean oil obtained a "green" or "fishy smell". Although American refined oil is much better than Northeast soybean crude oil, it is not as good as other salad oils and edible oils in the United States.
Horvath (1935) put forward a new method to remove bad ketones in the article "A new method for refining soybean oil". 1936 Morris Durkee, a great man in early soybean oil refining, commented on the advanced refining methods of A.E. stahly Refinery for many years, described that many improved processes consisted of five steps (neutralization, washing, decoloration, antifreeze and deodorization), and admitted that the biggest problem was how to avoid aftertaste. This problem was not solved until the late 1940s and early 1950s.
1936, in anticipation of the further development of the demand and application of soybean oil and soybean meal in industrial products, the U.S. government cooperated with the University of Illinois and 12 north-central states to establish the American Soybean Industrial Products Laboratory in the University of Illinois. In the next few years, many important research and development were carried out there. The regional soybean laboratory of USDA and several industrial laboratories have developed a promising new method called "fractional separation". A number of patents have been issued. It involves physically separating soybean oil into two fractions, one is saturated triglyceride, which can improve flavor and stability, and the other is mainly unsaturated triglyceride.
194 1 1 February, the war broke out between the United States and Japan, which cut off the import of edible oil and grease (especially coconut and palm oil) in the Pacific islands (especially the Philippines and East Asia). These areas accounted for about two-thirds of America's pre-war oil imports. The war inevitably led to a sharp increase in the demand for edible oil and fat. The American government widely mobilized people to grow soybeans. During the period of 1943, the domestic soybean oil production in the United States increased by 62%, surpassing the second linseed oil. Then at 1944, it surpassed the first cottonseed oil to become the main vegetable oil in the United States, and this situation has been maintained until today.
Although the soybean oil market is expanding, its taste is listed as the number one problem in the soybean industry in 1945, which will limit the future soybean production. Because of this taste problem, the wholesale volume of soybean oil was lower than that of cottonseed oil during the period of1935-1949 ~14%. In order to solve this key problem, on April 22nd, 1946 held the first meeting to discuss the flavor stability of soybean oil under the auspices of the Soybean Research Committee of Bismarck Hotel in Chicago, Illinois, USA and the National Soybean Processors Association (NSPA), and 28 researchers attended the meeting. Edward Dies, the chairman of the board, introduced the purpose of the meeting and emphasized the quick solution to the problem of soybean flavor stability.