水分含量及添加剂对面团玻璃化转变温度的影响

本实验应用差示扫描量热仪(DSC),测量了不同水分含量的面团的玻璃化转变温度以及NaCl、卵磷脂、抗坏血酸、明胶、海藻糖、单干酯及黄原胶等常见食品添加剂对面团玻璃化转变温度的影响。结果表明:水分含量为40%的纯精粉面团的玻璃化转变温度为-27.75℃,水分含量在38%～45%的玻璃化转变温度有逐渐降低的趋势。NaCl、抗坏血酸、海藻糖分别以5%、1%、3%加入面团以后,面团玻璃化转变温度分别为-13.68、-12.73、-15.74℃。加入明胶、单干酯、黄原胶时,面团的玻璃化转变温度提高并不明显,而卵磷脂的加入却降低了面团的玻璃化转变温度。

Effects of Water Content and Several Common Food Additives on Glass Transition Temperature of Dough

In this study, The dough’s glass transition temperature of dough was determineded by DSC (differential scanning calorimetry). The effects of water content, NaCl, ascorbic acid, 2,2-prehalose, gelatin, glycerol monostearate, xanthan gum and lecithin on glass transition temperature of dough were assayed also. The results showed that: glass transition temperature of dough with 40% water content is -27.75 ℃, and the glass transition temperature decreases with the water content when the water content is between 38% and 45%. When NaCl, ascorbic acid and 2,2-prehalose are added into the dough with the weight ratio of 5%, 1% and 3% respectively, the glass transition temperature of the dough are -13.68 ℃, -12.73 ℃ and -15.74 ℃, respectively. When gelatin, glycerol monostearate, xanthan gum is added, the increase of glass transition temperature of dough is not significant, but addition of lecithin decreases the glass transition temperature of dough.