Quick cooking rice by high hydrostatic pressure processing

Abstract

Jasmine rice was soaked for 0, 30, 45 and 60 min and then high hydrostatic pressure (HHP) processed, first at 300 and 400 MPa (for 2 and 4 min), and then a second HHP process was applied at 570 MPa for 20 min. The HHP-processed rice was heated in a microwave oven for 1.5 min, with a rice/water ratio of 1:2, and sensory evaluation and texture analysis were conducted. The quality of the pre-soaked rice and HHP-processed rice, before and after microwave heating, was obtained by measuring the degree of gelatinization with differential scanning calorimetry, and texture profile analysis. Also, the gelatinization and pasting properties of milled HHP-processed rice flour were determined using a Brabender Visco-amylograph. During soaking, the rice attained its highest moisture content (32.41 ± 0.43 %) in 30 min. It was shown that rice which was single HHP treated at 300 and 400 MPa had a better acceptance, in terms of grain shape, adhesiveness, cohesiveness and texture. In general, jasmine rice that had been HHP processed and then microwave heated for 1.5 min was more valued than jasmine rice just heated by microwave oven for 10 min, in terms of the grain shape, adhesiveness, cohesiveness, texture and overall quality.