摘要
应用差示扫描量热分析仪研究了锥栗原淀粉、直链淀粉、中间成分和支链淀粉的热力学特性。4个样品在-50～350℃的程序升温过程包含冰晶融化(-10～5℃)、糊化(40～100℃)和熔融裂解(250～310℃)3个吸热过程。当水分质量分数为65%时,它们的晶体融化峰值温度(TP)、终止温度(TC)和吸热焓(ΔH)均升至最高。对于相同的样品,当升温速率降低时,糊化温度向低温侧移动,且伴有肩状峰;糊化时升温速率越快,其凝胶体系的峰值温度(TP)、终止温度(TC)和吸热焓(ΔH)也越高,回生度越大;同样,糊化时降温速率越慢,凝胶体系的吸热焓(ΔH)增加,回生度增大。当糊化终止温度为100℃时,4个样品凝胶体系的DSC参数值均达到最低。锥栗原淀粉、直链淀粉、中间成分和支链淀粉凝胶体系的玻璃化转变温度(Tg)分别为-6.0、-7.1、-8.6和-7.9℃。
Differential scanning calorimetry （DSC） was applied to study thermodynamic characterizations of natural starch, amylose, intermediate constituent and amylopectin isolated from Castanea henryi. Programmed temperature process of C. hcnryi natural starch and its separative components during the scanning range between -50℃ and 300℃ included three endothermic phases,i, e. ,ice crystals melt （ - 10 -5 ℃ ） ,gelatinization （40 - 100℃） ,and fusing and thermal pyrolysis （200 -260 ℃）. The initial temperature （ To ）, top temperature （ Tp ）, final temperature （ Tc ） and melting enthalpy （△H） of the four samples increased the maximum at water content of 65%. For the same sample, gelatinization temperature shifted toward low temperature with decrease of heating rate and several shoulder peaks often accompanied. The more rapid was heating rate during the gelatination, the higher top temperature （ Tp）, final temperature （Tc ）,endothermic enthalpy （AH） and retrogradation degree of their gel systems were achieved. Meanwhile, if cooling rate during the gelatination declined, the endothermic enthalpy （△H） and retrogradation degree of their gel systems increased. At gelatinization temperature of 100 ℃, the DSC parameters of gel systems of the four samples decreased to the minimum. The glass - transition temperatures （ Ts ） of C. henryi natural starch, amylose, inter- mediate constituent and amylopectin were - 6.0, - 7.1, - 8.6 and - 7.9 ℃, respectively.
出处
《中国粮油学报》
EI
CAS
CSCD
北大核心
2011年第2期38-42,51,共6页
Journal of the Chinese Cereals and Oils Association
基金
湖南省教育厅大学生研究性学习与创新性实验计划项目(2008-241)
关键词
锥栗
原淀粉
直链淀粉
支链淀粉
热力学特性
Castanea henryi, native starch, amyolse, amylopectin, thermodynamic property
