以非糯性玉米淀粉、绿豆淀粉及皱皮豌豆淀粉为研究对象,采用差示扫描量热仪(DSc)测定了淀粉的热性质和回生性质,分析比较了3种淀粉化学组成、热性质及回生性质。DSC实验结果表明玉米淀粉、绿豆淀粉和豌豆淀粉的糊化熔点温度分别为(66.33±0.19)℃、(64.99±0.13)℃和(62.49±0.11)℃;峰值温度分别为(70.93±0.02)℃,(69.35±0.16)℃和(68.78±0.111℃;糊化焓变值分别为(13.48±0.62),(11.91±0.46)、(15.01±0.65)J/g,糊化焓变与直链淀粉含量呈显著相关性(相关系数为0.979,P〈0.01),淀粉糊化熔点及峰值温度则受直链淀粉含量、淀粉分子结构和聚合度及淀粉颗粒特性等因素的影响。在4℃贮藏过程中,玉米淀粉、绿豆淀粉和豌豆淀粉凝胶在7d时重结晶过程基本结束,淀粉回生焓变值与贮藏时间呈显著相关性(相关系数为0.811),淀粉回生焓变值与直链淀粉含量成相关性(相关系数为0.632),这些结果有助于通过调节淀粉基食品中直链淀粉含量和贮藏时间来控制较高含水量的淀粉基食品回生过程,进而掌握冷藏过程中淀粉基食品品质变化规律,提高淀粉基食品的食用品质。
The thermal and retrogradation properties of non-waxy corn starch, mung bean starch and wrinkled pea starch which determined by differential scanning calorimetry (DSC), were investigated, and compared the chemical composition, thermal properties and retrogradation properties. The DSC scanning results showed that the onset temperature of non-waxy corn starch, mung bean starch and wrinkled pea starch were (66.33±0.19) ℃, (64.99±0.13) ℃ and (62.49± 0.11) %, the peak temperature were (70.93±0.02) ℃, (69.35±0.16) ℃ and (68.78±0.11) ℃, and gelatinization enthalpy were (13.48±0.62),(11.91±0.46), (15.01±0.65) J/g, respectively. The thermal enthalpy value were related to amylose content (pearson correlation coefficient is 0.979, P〈0.01), and the thermal results indicated that the onset and peak temperature of starches were related to amylose content, molecule structure and degree polymerization, and granule characteristics. The retrogradation enthalpy value of starches indicated that the retrogradation process were finished within 7 days and the retrogradation enthalpy values were positively related to storage time (pearson correlation coefficient is 0.811, P〈0.01) when storage at 4 %, moreover the retrogradation enthalpy values were also related to amylose content (pearson correlation coefficient is 0.632). These results were very helpful for starch based food industry to control the food quality by storage time and amylose content of the starched food.