Why does the steamed bun turn yellow?

Pure alkali steamed buns are still quite popular in our lives, because everyone knows that steamed buns made with alkali are softer and more delicious than those made with baking powder. Some people find that when they steam steamed buns at home, they do not look white and plump, but a little yellow, which will affect the appetite. So what is the reason for the yellowing of steamed buns?

Yellowing of steamed buns is a common problem encountered by steamed bun processors, and even experienced steamed bun makers cannot avoid it. In summary, there are three main reasons why steamed buns turn yellow:

1. The problem of yellowing steamed buns will often occur when using the old dough fermentation process. This is mainly because the dough used to make the old dough contains not only yeast but also many other bacteria (such as lactic acid bacteria). After the dough is fermented, alkali needs to be added to neutralize it. If too much alkali is added, the steamed buns will turn yellow and smell alkaline.

2. The problem of flour quality. Some flour mills grind the flour too finely in order to pursue the whiteness of the flour, which results in the breakage of starch granules. When such flour is used to steam steamed buns, the buns will be relatively white and bright when they are just out of the pot, but will turn yellow after being left for a while.

3. The water quality in some areas is alkaline, and the steamed buns tend to turn yellow when they are reheated. When you encounter this problem, you can add an appropriate amount of white vinegar to the water.