Influence of low pressure cold plasma on cooking and textural properties of brown rice

• Decrease in the cooking time of brown rice
• Hydrophilic attitude was enhanced after the plasma treatment.
• Betterment in the textural quality of cooked rice
• Significant change in nutritive value was observed, but they may be irrelevant.

The aim of this research is to study the effect of low pressure cold plasma on the cooking and textural properties of brown rice at two different power levels (40 and 50 W) and different treatment times (5 and 10 min). Cold plasma processing of foods is an emerging non thermal technology mainly used to change surface properties of substrates and microbial inactivation. Proximate composition, cooking properties and textural characteristics of plasma processed brown rice were investigated. SEM, contact angle and surface energy analysis were done to study the changes in surface morphology of plasma treated rice. It was observed that after the plasma treatment the cooking time was reduced significantly from 29.1 min to 21.1 min with respect to plasma power and time of treatment. The increase in degree of gelatinization of the cooked samples supported the decrease in cooking time. The water uptake was increased from 2.2 to 2.36 g/g after the treatment. Textural parameters showed there is decrease in hardness from 40.47 N to 30.09 N and chewiness. The extent of plasma treatment was observed as decrease in contact angle and increase in surface energy, making surface more hydrophilic and thus rice grains absorbs more water resulting in lesser cooking time. Based on the results it can be concluded that plasma application can significantly change cooking and textural properties.Industrial relevanceThe present work is suitable for the instant rice production industries. This technology can be used by the industries designing rice cooker. This can also be used by the countries for cooking rice, where resources are scarcity.