Abstract In this experiment, apple was used as experimental materials and the tartaric acid of apple was extracted by water bath extraction and ultrasonic-assisted extraction. The extracting technical level was improved by orthogonal experiment. Moreover, acid-base titration was used to determine the total acidity. The results of the experiment showed that the extractive effect of water bath extraction was the best when the temperature was 80℃, the extracting time was 90 minutes, the mass of apple was 15 g, and the tartaric acid content was 4.476 3 g/kg correspondingly. About the ultrasonic-assisted extraction, the optimum extractive condition was that the temperature was 70℃, the time was 30 minutes, the mass of apple was 15 g, and the tartaric acid content was 4.791 8 g/kg.
