Preparation method of fermented apple juice for relieving alteration of intestinal flora

The invention discloses a preparation method of fermented apple juice capable of relieving alteration of intestinal flora, which comprises the following steps: cleaning apples, cutting and denucleating, taking 1/4 of the apples, steaming in water until apple blocks are slightly transparent, cooling to room temperature, peeling, juicing and filtering to obtain clarified apple pulp A and pomace A; adding a proper amount of lemon juice and cow milk into the rest, juicing, and filtering to obtain clarified apple pulp B and pomace B; mixing the pomace A and the pomace B, granulating, and dispersing into a sodium alginate solution to prepare fruit granules; and putting the clarified apple pulp B into a fermentation tank, inoculating lactobacillus delbrueckii subsp. Lactis, lactobacillus pentosus and bifidobacterium bifidum, fermenting for 2-3 days, mixing the obtained fermentation liquor with the clarified apple pulp A, homogenizing for 2-3 times at the treatment flow rate of 5-7L/h, mixing with the fruit grains, f