|Rice Utilization and
Product Development - 2008
Project Leader and Principal Investigators
Zhongli Pan,research engineer, USDA-ARS, Albany, CA
This ongoing project is focusing on further investigations of ultrasonic technology to develop new end products for rice.
Broken rice and rice bran are produced in large quantities as byproducts from rice processing. Currently, they have low economic value and are not well utilized. However, both of them are high in protein and could be used as raw materials for producing high-value functional food ingredients and nutritional supplements. Food protein-based molecules called polypeptides are effective at fighting hypertension and are safer than conventional drugs.
Ultrasonic technology has many advantages over conventional practices to extract proteins and to reduce the usage of enzymes in the production of polypeptides. This increases both the functionality of the end product and reduces production time needed for extraction.
Research in 2008 investigated ultrasonic treatment on the yield of extracted protein and examined the antihypertensive capability of polypeptides produced with ultrasonic technology. Ultrasonic treatment applied to protein extraction from rice flour increased yield as a function of power level and extraction time – up to 34 percent above conventional techniques. The yield was more than twice that of conventional extraction. The research concluded that ultrasonic-assisted extraction is an effective processing method to achieve high protein yield with reduced processing time.
Examination of the extracted protein with UV light showed that the ultrasonic treatment did not degrade protein structure yet enhanced its solubility, an attribute favorable for the production of polypeptides.
Subsequent experiments showed that ultrasonically produced polypeptides significantly lowered hypertension in rats.