Miller J, Nnanna I
J Nutr. 1983 Jun;113(6):1169-75. doi: 10.1093/jn/113.6.1169.
The relative biological value (RBV) of iron in egg yolk was compared with that of iron in ferrous sulfate in prophylactic assays with weanling rats. Egg yolk cooked by one of three different methods was used in each experiment: (1) yolk of eggs boiled in the shell, lyophilized, and mixed with other dry diet ingredients; (2) pasteurized yolk and other diet components steamed with 8 liters of water per kilogram of diet; and (3) pasteurized yolk and other diet ingredients baked with 0.5 liters of water per kilogram of diet. Diets containing three levels of egg yolk and four levels of ferrous sulfate were fed to different groups of rats for 1, 2, and 3 weeks. Response of dietary iron was calculated as the regression of hemoglobin iron gain on iron intake and the nutritional quality of egg iron relative to that of ferrous sulfate iron was evaluated by slope-ratio analysis. RBV was 61, 64, and 90%, respectively, for iron of egg yolk cooked by the three methods. The presence of ascorbic acid during heat treatment of the diets significantly increased RBV of yolk iron from 64 to 92% in experiment 2, and increased it to a value equivalent to that of ferrous sulfate in experiment 3.
在对断奶大鼠进行的预防性试验中，比较了蛋黄中铁与硫酸亚铁中铁的相对生物利用率（RBV）。每次实验使用通过三种不同方法之一烹制的蛋黄：（1）带壳煮鸡蛋的蛋黄，冻干后与其他干饲料成分混合；（2）巴氏杀菌蛋黄和其他饲料成分，每千克饲料用8升水蒸煮；（3）巴氏杀菌蛋黄和其他饲料成分，每千克饲料用0.5升水烘焙。将含有三个水平蛋黄和四个水平硫酸亚铁的饲料喂给不同组的大鼠1、2和3周。膳食铁的反应通过血红蛋白铁增加量对铁摄入量的回归进行计算，并通过斜率比分析评估蛋黄铁相对于硫酸亚铁铁的营养质量。三种方法烹制的蛋黄中铁的RBV分别为61%、64%和90%。在饲料热处理过程中添加抗坏血酸，在实验2中显著提高了蛋黄铁的RBV，从64%提高到92%，并在实验3中将其提高到与硫酸亚铁相当的值。
