This study was carried out to investigate milling's effect on the pasting properties and storage stability of dry-milled rice flour. Rice flour's moisture content was increased from 9.48% to 9.80% after going through a rice polisher, and the crude fat content of rice flour was decreased from 0.91% to 0.62% after going through a rice polisher. In the color index of rice flour, the rice polisher was only affected by yellowness. The pasting properties were verified through RVA, and it was confirmed that the use of a rice polisher had no significant effect on the pasting properties. As a result of observing the changes in fatty acid value, it was ascertained that the storage period could be increased using the rice polisher. These results suggest that the rice polisher can increase the storage period without changing the pasting properties.

The purpose of this study was to derive the conditions for manufacturing rice porridge with optimum properties after reheating. The characteristics of rice porridge according to the soaking time, water addition rate, heating temperature, heating time, and cooling conditions were compared using the ‘Samkwang’ cultivar. In Step Ⅰ, as the heating temperature increased, the weight change decreased and the viscosity increased, and the temperature known as the main factor of the gelatinization also appeared to affect the viscosity increase. In Step Ⅱ, the viscosity and the texture properties was not significantly different as the soaking time was reduced, and 10 minutes was suitable because of due to the shortening effect of the total process time. In Step Ⅲ, the residual heat was lowered by cooling after the rice porridge production, so the viscosity could be greatly reduced. Also, it was confirmed that the water addition rate of 900% and the heating temperature of 15 minutes were optimal manufacturing conditions. The next study will investigate the porridge processability of rice cultivars using these results.

The prevalence of chronic diseases has increased steadily over the last 20 years. The side effects of drugs used to treat chronic disease have always been a problem, owing to the need for long-term medication. Many studies have attempted to discover drugs from natural sources with fewer side effects. In this study, we investigated the possibility of using jujube leaf as a potential anti-diabetic drug source or food supplement. The IC50 values of acarbose and jujube leaf extract on a-glucosidase were 2.59 and 0.37 mg/mL, respectively. In vitro tests showed that the inhibition of a-glucosidase was maintained after the jujube extract was passed through a simulated digestive system, but no inhibition of a-amylase was observed either before or after the in vitro digestion. The jujube leaf extract showed mixed non-competitive inhibition. Jujube leaf extract is expected to be safer and cheaper than synthetic inhibitors.

The glucosidase inhibitors are currently interested owing to their promising therapeutic potential in the treatment of disorders such as diabetes, human immunodeficiency virus (HIV) infection, metastatic cancer, and lysosomal storage diseases. Among them, β-d-glucosidase inhibitors can be used to elucidate the mechanisms of various biochemical reactions and to treat the Gaucher disease as potential therapeutics. In this study, the natural β-glucosidase inhibitor was isolated from jujube leaf extract. The isolation and purification are vital for the structure analysis. The jujube leaf was extracted with hot water (95°C, 15 min). Then the natural β-glucosidase inhibitor was isolated using size exclusion chromatography and semi-preparative HPLC. In the first purification process, the 35 fractions were collected according to molecular size using PD-10 column packed with Sephadex G-25 medium. The strongest inhibition on the activity of β -glucosidase was observed at 6 and 7 fractions. The chromatogram of these samples showed that 3 peaks were observed comparing with baseline. For further purification, the strongest inhibitory activity peak was isolated using semi-preparative HPLC with VDS C18 column. Highly purified inhibitor, which can be used for structure analysis and characterization, was obtained. Further study is necessary to identify the natural β-glucosidase inhibitor in the jujube leaf extract.