We used to make zongzi there. Originally, we used soybean shells to burn into ashes, soaked in water with this ashes, and after precipitation, clean water was used to run zongzi rice. This is not only colorful, but also very fragrant, and it also has the effect of making zongzi not easy to spoil.

Later, everyone stopped farming and was too troublesome to buy the powder you mentioned in the market and put it in. I heard from my mother that it was almost the same as the alkali used when cooking porridge.