The purpose of this study is to optimize the rice starch and rice protein content ratio for the replacement of fish paste in eomuk using a response surface methodology. The experiment was designed based on the independent variables. The rice starch content (X1: 10, 20, 30%) and rice protein content (X2: 1, 3, 5%) were examined, along with the viscosity (Y1), color (Y2: L, Y3: a, Y4: b), and sensory evaluation of the dough (Y5: Color, Y6: Flavor, Y7: Off flavor, Y8: Taste, Y9: Hardness, Y10: Cohesiveness, Y11: Springiness, Y12: Chewiness, Y13: Overall acceptance), with the results being set as dependent variables. The p value of Y1, Y2, Y5, Y7, Y9, Y10, Y11, Y12, and Y13 showed a level of <0.05 excluding Y6 and Y8. R2 value was high at 0.80-0.95 so that these rice starch and rice protein contents were significantly affected in terms of the quality and sensory preference of eomuk; therefore, the optimal conditions of X1 and X2 were 19.99% and 2.91%, respectively. Under these optimal conditions, the predicted values of acceptance were Y5 (5.44), Y7 (5.36), Y9 (5.22), Y10 (5.46), and Y13 (6.11). These results will be the basis for building a method for obtaining a rice material. Also, they are expected to promote rice consumption through the development of processed foods using rice material.

The purpose of this study was to optimize the rice protein extracted using a response surface methodology. The experiment was designed based on a CCD (Central Composite Design), and the independent variables were the high pressure (X1, 0-400 MPa) and processing time (X2, 0-10 minutes). The results of the extraction content (Y1), residue content (Y2), and recovery yield (Y3) were fitted to a response surface methodology model (R2= 0.92, 0.92, and 0.93, respectively). Increasing the pressure and processing time has a positive effect on the extraction content (Y1), residue content (Y2), and recovery yield (Y3). Therefore, these high-pressure conditions (independent variables) can significantly affect the improvement in rice protein extraction efficiency. Thus, the optimal conditions of X1 and X2 were 400 MPa and 10 min., respectively. Under these optimal conditions, the predicted values of Y1, Y2, and Y3 were 62.93, 57.53 mg/g, and 91.76%, respectively.

In this study, dry-milled rice flour from different varieties (Samgwang, Boranchan, Hanareum, Dasan, Hangaru) and different particle sizes were used to manufacture Jeung-pyun and the quality characteristics were analyzed. The Jeung-pyun produced from Samgwang, Dasan and Hangaru milled rice flour showed highly dense pores. The Jeung-pyun produced from Hanareum only showed a significant difference according to the particle size. Samgwang, Boranchan and Dasan varieties with a particle size of 150 m showed a significant decrease in volume (p<0.05). Samgwang showed the lowest pH at all particle sizes (p<0.05). The sweetness of Samgwang varieties was the highest at 3.27-3.63°Brix (p<0.05). The hardness of Jeung-pyun increased with increasing particle size (p<0.05). The highest acceptance of Jeung-pyun in terms of volume and bitter taste was observed with Hanareum at a particle size of 50 m. When the particle size was 50 m, the overall acceptance was highest for Jeung-pyun made from Samgwang followed by Hanareum. The acceptance of all the sensory characteristics was high when the particle size of rice flour was 50 m. When the appearance of Jeung-pyun was measured, Samgwang showed a dense structure and low hardness. Hanareum showed an increasing volume and springiness. Overall Samgwang and Hanareum were found to be the most suitable varieties for the production of Jeungpyun.