Generally speaking, there are two ways to make dough. The first way is the traditional way, using "dough starter" to naturally ferment the dough on the mixed water surface, and then adding flour alkali and soda, mainly because the traditional way of dough mixing will make the flour sour, flour alkali can neutralize this sour taste, and soda plays a role in foaming, similar to the role of yeast. Another method is to use yeast. Compared with the first method, yeast is more controllable, not as difficult to control as soda. Most of the steamed buns sold in supermarkets and markets are yeast steamed buns. Therefore, the skill of dough making only has a great relationship with the added materials, and has nothing to do with milk and sugar.
You know, human saliva secretes many substances, including an enzyme that makes people feel "sweet". When we eat steamed bread, flour itself contains some sugar. With saliva, steamed bread tastes a little sweet. If you add a little more sugar, steamed bread will be delicious. In fact, the same is true of milk. The milk steamed bread sold in the supermarket is delicate because it is fermented with yeast, then mixed with milk or cream and steamed in a pot. Based on the strong controllability of yeast, the fermented bubbles are uniform and the steamed bread looks delicious.
However, yeast fermentation will also destroy the strength of flour itself. The best fermentation method is to ferment with flour starter, and then deacidify with flour alkali, so steamed bread tastes chewy and very strong. If sugar and milk are added to the flour, the steamed bread with moderate flour alkali will be whiter and taste better, but the taste will be much worse if more flour alkali is added. And this method is difficult to master. Maybe it's okay to mix noodles at home, but if you mix noodles in large quantities, try not to use surface alkali, otherwise the steamed bread will not taste good.