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Physico-chemical properties of the acetylated and raw starch were investigated with the chucheongbyeo and samkangbyeo. The solubility and swelling power was increased by acylation reaction. The light transmittance was higher in the acetylated rice starch. The blue value of chucheongbyeo and samkangbyeo rice starches were lowered to 10.9% and 16.0%, respectively, by the acylation reaction. The alkali number was 7.6 in the chucheonglrryeo rice starch and 7.2 in the samkangbyeo rice starch, whereas acylated starch in the same orders was 55 and 52, respectively. The hardness, adhesion, cohesion of starch gel was increased by the acylation reaction. The temperature of initial gelatinization of the acetylated chucheongbyeo and samkangbyeo rice starch was shown to 59 ℃ and 62 ℃ , respectively, lowering 5∼6℃ in temperature by the acylation. The viscosity as well as by the acylation reaction was raised 38% and 14%, respectively. The rice starch particles were shown to polygonal structure. But it were deformed in the acylated starch, and was completely destroyed in the starch which is by gelatinized for 30 min. at 70℃.
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