VitC在蔬菜汤中的变化规律

A Study on the Fluctuations of VitC Contents in Various Vegetable Soups

目的 了解汤中VitaminC(VitC)的变化规律。方法 模拟家庭中蔬菜汤的烹饪过程 ,采用 2 ,4—二硝基苯肼法测定VitC的含量。结果 7种蔬菜在煮汤过程中VitC含量均有损失 ,鸡毛菜VitC损失量最大 ,番茄VitC损失量最小。 7种蔬菜汤VitC含量也随多次加热而有所下降 ,鸡毛菜汤VitC损失最多 ,小青菜汤VitC损失最少。番茄汤VitC含量经多次加热后高于其初次煮沸时汤内VitC含量 ,但番茄VitC含量递减。生菜生吃的营养价值最高。

Objective To study the fluctuations of Vitamin C (VitC) contents in various vegetable soups.Methods The cooking of vegetable soups in families was imitated.VitC content of vegetable soups was determined by 2,4-dinitrophenylhydrazine.Results The contents of VitC in 7 different vegetables including jimaocai,tomato,lettuce,pak choi,towel gourd,wax gourd,green in their soups dropped during cooking . The highest loss of VitC content was one kind of vegetable called jimaocai in Shanghai in its soup.The lowest losses of VitC contents were tomato and greens soup respectively.After 2～3 heatings,the contents of VitC in tomato soup was still higher than that of tomato soup which was just cooked.But the VitC content in tomato decreased progressively.Taking fresh lettuce supplied highest VitC content than all other vegetables.Conclusion The results helped to popularize rational health diet.