Abstract:A compound oral liquid was prepared with purple sweet potato and mulberry as the main raw materials，and the release law of active substances and the changes in antioxidant activity were detected by the method of in vitro simulated gastric and intestinal digestion.The results showed that in the context of the mass ratio of purple potato extract to mulberry juice of 4∶3，the highest sensory evaluation score was 83.42 under the following conditions:95.98% purple potato extract and mulberry juice，4% white granulated sugar，and 0.02% citric acid.In the gastric digestion of the compound oral liquid，the content of flavonoids and anthocyanins and antioxidant capacity were significantly improved（p＜0.05）.In intestinal digestion，the total phenol content increased by 4.06%，the flavonoid content decreased by 8.34%，and the anthocyanin content decreased by 22.18%.Moreover，the antioxidant capacity was significantly improved（p＜0.05）.Correlation analysis showed that in gastric digestion，the antioxidant capacity was positively correlated with the content of flavonoids and anthocyanins，and in intestinal digestion，the antioxidant capacity was significantly positively correlated with the content of total phenols（p＜0.05）.In conclusion，simulated gastric and intestinal digestion was conducive to the release of active substances in the compound oral liquid，and the digestive products possessed good antioxidant activity.