Soy Hypocotyls Used to Create Inexpensive Soy Protein Isolate

Research conducted by scientists from Southern Yangtze University, Wuxi, China, and the Florida Department of Citrus, Lake Alfred, have shown that soy hypocotyls, a byproduct of the soy protein industry, might prove a viable alternative to protein isolates. The results of this research, Preparation of isoflavones enriched soy protein isolate from defatted soy hypocotyls by supercritical CO₂, were published in the June issue of LWTFood Science and Technology, the journal of the Swiss Society of Food Science and Technology.

Soy hypocotyls are rich in isoflavones, and the researchers sought to develop them into a value-added functional food, soy protein isolate (SPI). The researchers noted that they did not know if any other studies to date that have reported on the creation of isoflavone-enriched SPI directly from soy hypocotyls.

The hypocotyl is a portion of a germinating plant that grows upward and eventually develops into the stem (whereas the radicle grows downward and develops into the root). Due to its bitterness, processors traditionally remove the hypocotyl from soy during production of SPIs. By using supercritical CO2as opposed to solventsthe researchers were able to reduce the level of bitterness in the resultant defatted soy hypocotyls. They report that the process removed the aldehydes, ketones, furans and alcohols responsible for bitterness. Use of supercritical CO₂ is also a less-expensive alternative to solvent extraction.