In this study, researchers from Kasetsart University in Thailand investigated the effects of ultrasonic treatment and enzymatic treatments using three different enzymes on the structure and cooking quality of Oryza sativa (brown rice). The results of their study were published in the Journal of Food Processing and Preservation.

• Brown rice is usually soaked in water before cooking.
• To improve its water uptake, volume expansion, and texture during and after cooking, the researchers subjected brown rice to ultrasonic treatment (UT) and enzymatic treatments (ET) using cellulase, glucoamylase, and a-amylase.
• While all of the treatments affected the pasting properties of brown rice and the structure of its grain surface, only UT and a-amylase treatment affected the starch granules inside the grain.
• Brown rice that underwent UT had higher water uptake and volume expansion during cooking than brown rice subjected to ET.
• On the other hand, both UT and ET reduced the hardness of brown rice after cooking.
• Brown rice subjected to a-amylase treatment was the softest among the cooked treated brown rice.
• Although UT reduced the hardness of cooked brown rice and increased its volume expansion, the a-amylase-treated brown rice still received the highest liking score.
• Principle component analysis also revealed that a-amylase-treated brown rice is more preferable than the other treated brown rice.

Based on these results, the researchers concluded that a-amylase treatment can potentially become a novel technology for the development of high-quality brown rice.

Dang LTK, Therdthai N, Ratphitagsanti W. IMPROVEMENT OF STRUCTURE AND COOKING QUALITY OF BROWN RICE USING ULTRASONIC AND ENZYMATIC TREATMENTS. Journal of Food Processing and Preservation. 28 October 2018;42(11). DOI: 10.1111/jfpp.13814