The invention discloses a preparation method of freeze-dried Chinese wolfberry. The preparation method comprises the following operating steps: (1) preparing a compound dietary alkali solution, namely preparing a
mixed solution by using
sodium carbonate and
potassium carbonate with the
mass concentrations of respectively 50%, and then adjusting a pH value to 8-9; (2) soaking Chinese wolfberry in the compound dietary alkali solution, wherein the weight ratio of Chinese wolfberry to the compound dietary alkali solution is 1: (1-1.5), soaking for 30-50 minutes,
fishing up, draining off water, cleaning by using drinking water till the pH value of the surfaces of Chinese wolfberry is 7, draining off water, weighing, and putting on plates; (3) freezing for 4-6 hours at the temperature of subzero 37-39 DEG C; and (4) carrying out vacuum freeze-
drying treatment on the frozen Chinese wolfberry, and taking out from warehouses, thus obtaining the finished product. The preparation method has the beneficial effects that compound dietary alkali is used for removing paraffin, a heating gradient technology of performing sequential heating, cooling and vacuum-degree reduction is adopted during vacuum
freeze drying, so that the freeze-dried Chinese wolfberry is complete in size, and unchanged in color,
flavor and nutritional ingredients, and when being directly eaten, the freeze-
drying Chinese wolfberry is crisp and palatable and is
nourishing food suitable for eating by people of all ages and visiting friends and relatives.