Study of Surface Morphology of Low-Pressure Plasma Treated Rice by SEM and Contact Angle Measurement

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W. Arworn


This study focused on using low-pressure plasma processing on polished “white” rice and unpolished “riceberry” brown rice. Plasma treatment reduced the water contact angle on riceberry rice from 120.6°±1.0° to 89.8°±1.5°. Scanning electron microscope (SEM) images showed morphology of an external surface and a cross sectional view of the interior just below the surface of a rice kernel. The SEM image revealed a µm thin layer, 10-µm square-like pockets, and an endosperm of a few-mm across. The underlying pockets contain a lot of starch granules. SEM images also showed many pores on the top surface opening down to the pocket-like structure underneath after low-pressure plasma treatment. This effect caused the rice kernel to be more hydrophilic and agreed well with lower water contact angle. This work has demonstrated the feasibility of applying low-pressure plasma to improve the cooking quality of rice.

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How to Cite
Arworn, W. Study of Surface Morphology of Low-Pressure Plasma Treated Rice by SEM and Contact Angle Measurement. Microsc. Microanal. Res. 2017, 30, 33-36.
Original Articles


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