食物b的来源：酵母粉，蛋黄，肉，牛奶，黄豆，全谷类。

Food sources of B: Yeast powder, egg yolk, meat, milk, soy, whole grains.

结论即食酵母粉对小鼠的免疫活性有显著的增强作用。

Conclusion Instant yeast show the effect to enhance the immunity of mice.

一踏进农舍，我就闻到了奶奶专门为我做的小面包散发出来的酵母粉味道。

Stepping into the farmhouse, I can smell the yeast rising on a miniature loaf of bread Grannie has made just for me.