不同变性淀粉对冷冻面团热力学特性的影响

采用差示扫描量热法(DSC)研究4种不同种类变性淀粉对冷冻面团热力学特性(玻璃化转变温度、冰晶融化特性和可冻结水含量)的影响。结果表明,冷冻面团的玻璃化转变温度在-30℃左右,不同变性淀粉对冷冻面团玻璃化转变基本无明显影响;添加5%马铃薯羟丙基淀粉、木薯羟丙基淀粉和木薯醋酸酯淀粉可以显著降低冷冻面团冰晶融化范围,面团中形成的冰晶大小更加均匀;冷冻面团可冻结水含量随着马铃薯醋酸酯淀粉和马铃薯羟丙基淀粉添加量的增加呈降低趋势,添加10%木薯羟丙基淀粉时,面团可冻结水含量显著低于空白组,而木薯醋酸酯淀粉对面团可冻结水含量无显著影响。

Effect of different kinds of modified starch on calorimetric parameters of frozen dough

The effect of 4 different kinds of modified starch on calorimetric parameters(glass transition temperature,ice-melting properties and freezable water) of frozen dough was studied by Differential Scanning Calorimetry(DSC).The glass transition of frozen dough occured at the temperature around-30℃,and there was no difference between the control and modfied starch-substituted doughs.Dough substituted with 5% hydroxypropylated potato starch,acetylated tapioca starch and hydroxypropylated tapioca starch had a narrower ice melting range than the control,suggested a more homogeneous ice crystal structure in these products.Freezable water amount of frozen dough decreased with the increase of acetylated potato starch and hydroxypropylated potato starch content.Dough substituted with 10% hydroxypropylated tapioca starch which had lower freezable water amount than the control.However,acetylated tapioca starch had little effect on freezable water amount of frozen dough.