Does the subject want to ask "what is acid control"? I like sour food. According to relevant data, Nanning sour fruit is a traditional food with a long history, which refers to pickled vegetables and fruits, that is, sour products, which is the name of Nanning local vernacular. "Sour fruit" refers to something, and Nanning sour fruit refers to something sour. People in Nanning have a long history of eating sour products, because Nanning is located in southern Xinjiang and the climate is wet and cold for many years. Therefore, local people depend on it.