대두단백질, 전분, 수분을 조합하여 만든 모형식품에 보습제 종류 및 이의 농도에 따른 수분활성도의 변화를 전기습도계법으로 측정하였다. 모형식품의 수분활성도는 NaCl이 Sucrose보다 강하효과가 크게 나타났으며 성분간에는 단백질, 전분혼합물$(P_1S_1)$에서 수분활성도 강하효과가 높게 나타났다. 또한 용액의 첨가량이 50%에서 70% 범위에서 모형식품의 성분비, 용액 첨가비, 용질의 농도와의 다중회귀식을 다음과 같이 얻었다. $NaCl;E(Aw)=0.9317-3.48{ imes}10^{-3}X-1.019{ imes}10^{-4}X^2-2.217{ imes}10^{-4}Y+3.924{ imes}10^{-6}Y^2-7.163{ imes}10^{-6}Z^2$ $Sucrose;E(Aw)=0.9259+1.715{ imes}10^{-4}X-3.317{ imes}10^{-5}X^2+2.451{ imes}10^{-4}Y-1.604{ imes}10^{-6}Y^2+1.076{ imes}10^{-6}Z^2$ X : solute concentration(%), Y : {starch/total solid (starch+protein)}${ imes}$100 Z : solution ratio of model food(%) 이때 $R^2$은 각각 0.910, 0.935이었다.
This study was to predict water activity of gelatinized model foods containing moisture, protein and starch with different concentration of humectants such as sodium chlorife and sucrose. The water activity of each samples were determinded by electrical hygrometry. The degree of lowering water activity in model foods with humectant solutions was following order as NaCl>sucrose. Model food $P_2S_1$ was predominant in depression of water activity by humectants than other model foods. The multiple regression equations between water activity and different humectants concentration, compositions and solution ratio of model foods were obtained and $R^2$ values were higher than 0.91.
