Watermelon rind candy sauce. Select fresh watermelon rind, remove the outer skin and flesh, wash, cook and mash into mud. According to every 5 kilograms of sauce mud with 3 kilograms of sugar, citric acid 250 grams of the proportion of the mixture, so into a large aluminum pot slowly heated over moderate heat until the water evaporates and thickens as a paste. In the heating process should be constantly stirring, in order to prevent too much fire caused by the paste pot or uneven mixing. When the melon puree boiled into, should be loaded into the can while hot, the can is placed in a pot of boiling water heating exhaust, exhaust gas after the cover solid can cover, steam more than 30 minutes to sterilize, and finally removed and placed in a cool, ventilated place, to be cooled and can be eaten.