A simplex-lattice mixture design was applied to blend three varieties of rice; Ilpum (IP), Goami2 (G2) and Baegjinju (BJJ) all of which have very different physicochemical properties from one another. G2 and BJJ are mutant rice developed from IP. Increasing G2 portions in a rice blend increases indigestible carbohydrate contents. Blending at least 33.3% of G2 to either IP or BJJ increased indigestible carbohydrates, which were approximately $3.55{pm}1.31;to;4.57{pm}0.37$(g/100 g), respectively. Consumers rated higher than 6.0 (=like slightly) for the IP alone and binary blends of IP and BJJ, whereas less than 5.0 (=dislike moderately) for the blends containing G2 rice, indicating that consumers would not accept rice blends containing higher G2 portions. However, although blends with G2 were given lower consumer ratings, a rice blend with G2 could have health benefits in terms of nutritional and functional properties due to the higher indigestible carbohydrate contents.