澳洲坚果果仁粉水分解吸-吸附等温线的测定与分析

Determination and analysis of water desorption and adsorption isotherms of macadamia nut kernel flour

为给澳洲坚果果仁粉的干燥和贮藏条件的确定提供技术依据,试验测定了其在室温(25℃)下的水分解吸-吸附等温线。采用非线性回归的方法,应用常见的BET、GAB、Halsey、Henderson、Oswin和Smith模型对试验所得解吸-吸附等温线进行拟合分析,以确定最佳拟合模型及其参数。结果表明,其解吸等温线属于国际理论和应用化学联合会分类的第Ⅱ种类型,其吸附等温线属于第Ⅲ种类型,解吸-吸附滞后现象属于H3型;GAB模型是其最佳的解吸等温线拟合方程,Henderson模型是最佳的吸附等温线拟合方程;GAB模型拟合解吸等温线的参数A、B、C分别为8.2439、0.4815、1.3545。Henderson模型拟合吸附等温线的参数A、B分别为0.3006、0.8682。

In order to provide technical data for macadamia nut kernel flour drying and preservation, adsorption and desorption isotherms of macadamia nut kernel flour at room temperature （25℃） were determined. Non-linear regression analysis was used to evaluate the fitness of the commonly used models as BET, GAB, Halsey, Henderson, Oswin and Smith based on the experimental data, and to determine the best models and their parameters. The results showed that the obtained desorption isotherm was of type Ⅱ, and the adsorption was of type Ⅲ according to IUPAC classification. The hysteresis loop was of type H3. The best model fitted for desorption isotherm was GAB model, and that for adsorption was Henderson model. The parameters （A, B, C） of GAB model for desorption isotherm were 8.2439, 0.4815 and 1.3545, respectively. The parameters （A, B） of Henderson model for adsorption isotherm were 0.3006 and 0.8682, respectively.