Differential Scanning Calorimetry (DSC) is currently the most accurate method for testing the gelatini-zation temperature (GT) of rice flour. However, three important factors, including rice flour weight with water volume and the speed of temperature rise in DSC,were differently used in many experiments. Orthogonal design was introduced in present experiment to determine the best conditions for the smallest relative standard deviation (RSD) of TAQ20 DSC. The results indicated that the GT measurements could be influenced by these three important DSC conditions. The combination of 14 μL distilled water with 3.0 mg rice flour and 10 ℃/min speed of temperature rise was the best DSC experimental condition because of the smallest RSD of the GT in each experiment combination. 21 indica rice flour samples were used for analyzing GT by this best DSC condition,and their alkali spreading value ( ASV) and amylose content (AC) were also determined. The results also showed that the correlation coefficients between GT and ASV or AC were -0.75 * * * or 0.51 * respectively,which meant that GT was significantly negative correlated with ASV,but positive with AC.%差示扫描量热仪是目前米粉糊化温度测定中最为准确的一种方法,而目前研究中所使用的样品量、加水量和升温速率有着较大差异,利用正交设计方法确定了TAQ20型差示扫描量热仪的最小相对标准偏差试验条件.结果表明样品量、加水量和升温速率等3个因素的变化对糊化温度结果有一定的影响.比较各个组合的相对标准偏差值,选出3个因素的最佳组合为14μL水、3.0 mg米粉和10C/min升温速率.应用这一测定条件,测定了21份籼稻米粉的糊化温度.相关分析表明,糊化温度与碱消值和直链淀粉含量的相关系数分别为r=-0.75***和r=0.51*,说明糊化温度与碱消值之间存在极显著负相关、与直链淀粉含量则表现为显著正相关.
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