The process was further applied for treating soybeans prior to oil extraction. It was concluded that the quality of the crude oil obtained from the pretreated beans in terms of oxidation products, free fatty acids and nonhydratable phospholipids was such that the alkali treatment step in the refining process could be circumvented. The improved quality of the crude oil was attributed to the inactivation of phospholipase D, lipoxygenase and lipase. The residual defatted flakes showed low levels of trypsin inhibitor activity and could be used directly as food or feed.
Finally, the involvement of phospholipase D in the hydrolysis of phospholipids and formation of nonhydratable phospholipids in soybeans was elucidated by radio(chemical) methods, as well as thin layer chromatography and densitometry. The presence of an active, soluble form of the enzyme with isoelectric point 4.8 was shown by isoelectric focusing.
|Qualification||Doctor of Philosophy|
|Award date||19 Jun 1985|
|Place of Publication||Wageningen|
|Publication status||Published - 1985|
- heat treatment
- infrared radiation
- soyabean oil