Method for preparing stable-type vitamin A microcapsules continuously

A method for continuously preparing stabilized vitamin A microcapsules, characterized in that the method comprises the following steps:

• 1) under the protection of nitrogen gas, continuously adding vitamin A crystals and an antioxidant in a weight ratio of 100:1˜5 into a crystal melter, melting at 65˜75° C., to form vitamin A melting oil containing the antioxidant;
• 2) dissolving gellable modified starch in water at 65˜75° C., to form aqueous solution of 30˜40% modified starch, and deoxygenating at a vacuum of −0.07˜−0.08 MPa for 1˜2 hours;
• 3) pumping the vitamin A melting oil into a high gravity rotary packed bed emulsifier equipped with a liquid distributor;
• meanwhile, pumping the deoxygenated aqueous solution of modified starch into the same high gravity rotary packed bed emulsifier, to obtain a vitamin A emulsion at the outlet, and the weight ratio of the vitamin A melting oil to the aqueous solution of modified starch is 1:3˜9;
• and
• 4) continuously atomizing and spraying the vitamin A emulsion into a cooled starch bed for granulation, then performing fluidized drying and gelation treatment in a fluidized bed at 65˜75° C. using nitrogen gas as drying medium, to obtain the stabilized vitamin A microcapsule,
• wherein the antioxidant is ethoxy quinolone, tocopherol, BHT or BHA.