การพัฒนากระบวนการผลิตผลิตภัณฑ์ข้าวหุงสุกเร็ว โดยใช้เทคนิคสนามไฟฟ้าพัลส์

Abstract

This research aimed to study the application of pulsed electric field (PEF) for the process development of quick-cooking rice product. In addition, the derived product was determined for physicochemical properties, in vitro digestibility, as well as sensory attributes. Four varieties of rice, including Kum Chao Mor Chor 107, Jasmin 105, Kum Doi Saket, and Sanpatong 1, were studied. A three-level three-factor Box–Behnken design were chosen to evaluate the effect of three independent variables, including pulse number (X1, 2,000-6,000 pulses), electric filed strength (X2, 6-10 kV/cm) and frequency (X3, 3-15 Hz) on the cooking time (min) and full grain portion as response values. The optimal condition was obtained by using Response Surface Methodology (RSM)

As a result, the number of pulses and frequency were the most significant factors affecting those response values (p<0.05). The optimal condition for quick-cooking rice production consisted of 2565-5079 pulses, electric filed strength of 6-8 kV/cm, and frequency of 4.4-15 Hz. This optimized process could reduce the cooking time for about 3.9-4.3 folds, as well as retain the full grain portion for about 66.33-96.67%. The water uptake ratio and cooking loss of the derived rice were 0.85-2.12 and 1.30-12.08%, respectively. Moreover, the hardness of four PEF-treated rice samples were significantly decreased (p<0.05). The remained vitamin B1 and B3 contents found in PEF-treated rice and freeze-thawed rice (comparative method) were not significantly different (p>0.05). Furthermore, PEF treatment was efficient to improve the in vitro digestibility of protein and carbohydrate. A rapid digestible starch (RDS) tended to increase; meanwhile, a slowly digestible starch (SDS) was significantly reduced (p<0.05). The quick-cooking rice obtained by the developed PEF treatment was higher accepted, in terms of sensory evaluation, than that one from freeze-thawing process.

This study revealed the efficiency of PEF for the application as a new strategy for the process development of rice product. As the derived rice can be comfortably quickly cooked with obtaining the soft texture, so it is expected in meeting nowadays consumers demand particularly working-age and aging populations.