Physicochemical properties of aromatic rice prepared using different milling recoveries and roasting procedures

Abstract

In this study, the physicochemical properties of aromatic rice prepared using different milling recoveries and roasting procedures were investigated. As a result, we found that the L value of different milling recoveries of aromatic rice (BA-1, BA-2, BA-4, and BA-6) increased as the aromatic rice (BA-0) decreased, while the a and b values decreased as the different milling recoveries increased. The major contributors to the different milling recoveries of aromatic rice were total polyphenol (28.11-33.84 mg/100 g), amylose (24.97-31.06 mg/100 g), total starch (68.27-73.04%) content. In addition, three different roasting methods were applied; the aromatic rice was roasted at 250℃ for 0 min (BAR-0M), 15 min (BAR-15M), or 30 min (BAR-30M). As a result, the color in terms of the L value decreased, whereas the a and b values increased. Also, the total phenolic and flavonoid contents in BAR-30M (41.65 mg/100 g and 22.30 mg/100 g, respectively) were higher than those in BAR-0M (33.00 mg/100 g and 20.78 mg/100 g, respectively). Similarly, the amylose and total starch contents in BAR-30M (26.10 g/100 g and 81.81%, respectively) were higher than those in BAR-0M (22.10 g/100 g and 74.26%, respectively). Furthermore, the DPPH, superoxide radical scavenging activity, and ferric reducing antioxidant potential of BAR-0M at 5,000 μg/mL were found to be 67.78%, 52.90%, and 0.79 mM, respectively. Based on these results, we can conclude that in order to provide the best physicochemical characteristics of aromatic rice, it should be manufactured in the following conditions: 20% milling recovery of the aromatic rice and roasting at 250℃ for 30 min.