Preparation method of bromelain leaching liquor and stabilization protective agent used therein

The invention discloses a preparation method of bromelain leaching liquor and a stabilization protective agent used therein. The preparation method comprises following steps: adding water and a bromelain active stabilization protective agent in the raw materials, mixing, pulverizing, crushing to get juice, adjusting the pH value of the obtained juice to a range of 3.0 to 6.5, keeping the temperature in a range of 4 to 30 DEG C for 5 to 40 minutes, and filtering so as to obtain the bromelain leaching liquor. The preparation method can fully utilize the function of the bromelain active stabilization protective agent, decreases the inactive rate of bromelain in the consequent separating and purifying operations, maintains the activity of bromelain and effectively increases the enzyme activity recycle rate of bromelain in the leaching liquor. The bromelain active stabilization protective agent can effectively protect the activity of bromelain, and largely increases the enzyme activity recycle rate of bromelain in the bromelain leaching liquor.