Colman N, Green R, Metz J
Am J Clin Nutr. 1975 May;28(5):459-64. doi: 10.1093/ajcn/28.5.459.
The absorption of folic acid from maize, rice and bread fortified with pteroylglutamic acid was compared with that of an aqueous solution of pteroylglutamic acid in the same subjects. Feeding fortified maize and rice produced similar increments in folic acid concentration, which were approximately half those observed with the pteroylglutamic acid solution. Fortified bread produced a lower increment. Pteroylglutamic acid was found to resist destruction by boiling and baking at temperatures and times used for the conventional preparation of such foods. However, baking for longer periods resulted in a loss of folic acid activity. It is concluded that fortification of staple foods with folic acid may offer a practical adjunct to nutritional programs designed to improve the intake of essential nutrients.
在同一批受试者中，对食用添加了蝶酰谷氨酸的玉米、大米和面包后叶酸的吸收情况，与食用蝶酰谷氨酸水溶液后的吸收情况进行了比较。食用强化玉米和大米后，叶酸浓度有相似程度的增加，约为食用蝶酰谷氨酸溶液后所观察到增幅的一半。强化面包产生的增幅较低。研究发现，在用于此类食物常规制作的温度和时间条件下进行煮沸和烘焙，蝶酰谷氨酸能抵抗破坏。然而，烘焙时间延长会导致叶酸活性丧失。得出的结论是，用叶酸强化主食可能为旨在改善必需营养素摄入量的营养计划提供一种实用的辅助手段。
