Method of preparing concentrated clear red jujube juice with high cAMP content

The invention discloses a method of preparing concentrated clear red jujube juice with high cAMP content, which comprises the following steps: taking out red jujube after rehydration, denucleating and then crushing pulp for preparing the red jujube thick liquid; conveying the red jujube after enzymolysis by pectinase into a juicer for squeezing, and filtering to obtain the red jujube juice; adding pectinase, amylase and cellulose into the red jujube juice for heat-preservation and enzymolysis for 60-90 minutes; and clearing, conducting concentration sterilization, and finally bulking. The concentrated clear red jujube juice prepared by the invention is clear and transparent, has the cAMP content being larger than or equal to 100 mg/Kg and soluble solid state material being larger than or equal to 60.0 Brix, is deposit-free and suspension-free, has brownish red color and does not have impurities which can be seen by naked eyes; and the concentrated juice is diluted to the soluble solidstate material being 60.0 Brix, and the juice has inherent fragrance and flavor of red jujubes and is free from extraneous odor.