The purpose of this study was to determine the optimal mixing conditions for three different amounts of mulberry juice, sugar, and agar powder for Yanggaeng prepared with mulberry juice. The experiment was designed according to the central composite design for estimating the response surface, which demonstrated 16 experimental points including 2 replicates for mulberry juice, sugar and agar powder each?? The mechanical and sensory properties of test materials were measured, and these values were applied to the mathematical models. A canonical form and perturbation plot showed the influence of each ingredient on the final product mixture. Measurement results of the mechanical properties showed a significant increase or decrease?? in pH, sugar content, water content, viscosity, l-value, a-value, b-value, hardness, springiness, chewiness, gumminess, cohesiveness. Also the sensory measurements showed a significant improvement?? in appearance, flavor, color, sweetness, texture, overall quality. As a result, the optimum formulation by numerical and graphical methods was calculated as mulberry juice 41.99 g, sugar 90.00 g, agar powder 3.18 g.

The principal objective of this study was to determine the optimal mixing condition of two different amounts of cabbage and rice flour for the preparation of a cabbage cream soup. The experimental design was based on the central composite design methodology of response surface, which included 10 experimental points, including two replicates for the cabbage and rice flour. Physiochemical and sensory properties were measured, and these values were applied to the mathematical models. A canonical form and perturbation plot showed the influence of each ingredient on the mixed final product. Water content and pH values increased with increasing quantities of rice flour. Neither cabbage or rice flour affected the L and a values, but the b value increased with greater quantity of both ingredients. Viscosity increased with increasing added cabbage. Sensory evaluation results were significant in the predicted model for flavor (p<0.05), concentration (p<0.01) and overall quality (p<0.01). As a result, the optimum formulations by numerical and graphical methods were calculated as 111.79 g cabbage and 8.99 g rice flour.