超市的面粉有bleached and unbleached。我一般都是买unbleached. 那么有什么不同呢？
Bleached flour is typically refined, meaning that the nutrient-rich bran and germ of the wheat kernel have been removed, stripping the grain of many of its valuable vitamins and minerals and leaving only the endosperm.
Unbleached flour may or may not be refined.
Both types are first milled, which is a process that involves grinding grain into a fine powder.
Next, bleached flour is treated with chemical agents like benzoyl peroxide, potassium bromate, or chlorine, which helps speed up the aging of the flour. Flour is aged to improve certain qualities for baking. This chemical process significantly changes the taste, texture, and appearance of the final product, as well as its nutritional profile and potential uses in baking. 南方人一般都喜欢白白胖胖，松松软软的包子和馒头，这种面粉就可以做出这个效果。
Unbleached flour is aged naturally after the milling process is completed. Natural aging takes significantly longer than the bleaching process, which is why bleached flour was created. 这种面粉有点发黄，不过黄色很淡，为了做出来白一点可以用牛奶发面. 这种面做出来的面食比较筋道，非常适合我的口味。
为了给大家看看Unbleached flour 做的包子颜色，我今天用自来水发的面。