Preparation process of white sour soup

The invention relates to a preparation process of white sour soup. The preparation process comprises the following steps: cleaning and disinfecting a jar for later use; boiling running water, pouring water into the jar cleaned in step S1 after cooling to 39-41 DEG C; cleaning sticky rice, soaking for 3 h in water, taking out and draining water, putting into a food steamer and steaming the sticky rice; cooling the steamed glutinous rice, separating into clumps of 50 g, putting into the jar, adding saccharomycetes simultaneously for fermentation, putting the jar into a fermentation chamber; controlling the temperature of the fermentation chamber at 30-36 DEG C, stabilizing the acid content in the jar at 0.5% when the glutinous rice ferments on the fourth day; when the white sour soup ferments and stabilizes on the fifth day, pumping a supernatant liquid of the sour soup into a hollow jar with a stainless steel pipe for precipitation, adding warm boiled water and the glutinous rice many times for natural ferment