Pectin has a wide range of uses in food, medicine, and household chemistry. It has been used as a scarce material in domestic and foreign markets. It can extract 40 tons of pectin per 10,000 tons of watermelon rind, worth 4 million yuan. The production process is as follows: 1. Clean the fresh watermelon rind with water to remove impurities such as sediment and dust. 2, steam through the washed raw materials into the steamer steam for 30-40 minutes, to melon soft, there is precipitation of water for the degree. 3, squeeze the raw material after steaming dried as much as possible to remove the water. 4, the hydrolysis will be dried raw materials placed in corrosion-resistant containers, add water 3-4 times, add acid pH is about 2 (pH) heating near boiling, keep a certain time. The acidity, temperature and time in this step should be tested and carefully controlled. If the acidity is large and the temperature is high, the time is short. Otherwise, the pectin will decompose excessively; when the temperature is low, the time will be longer, otherwise the pectin will not be hydrolyzed. 5. The filter is squeezed and filtered with a cloth bag and the filtrate is collected. The filter residue after pressing can be hydrolyzed twice and filtered. The operation is the same as above except that water is added twice. 6. Decoloration Combine the filtrates obtained twice, add 0.3-0.5% of activated carbon, heat to 55-60°C, and decolorize for 30 minutes. 7. Concentration The decolored liquid is concentrated in vacuo to a solid. 8. Alcohol precipitation In the concentrated solution, 90% ethanol solution was added (the amount was 1 or more times more than the concentrated solution). Immediately after adding ethanol, pectin flocculated. Wait for a while before pressing. 9. Squeeze the flocculent pectin into the batt bag to remove the liquid. Pay attention to the recovery of ethanol in the liquid. 10, alcohol wash will be squeezed pectin, with 95% ethanol (the amount of pectin 1 times), wait a while, squeezed ethanol. 11. Drying Put the solid pectin in the enamel plate and bake it at a temperature of 65°C-75°C until the moisture content is below 8%. 12. Grinding The pectin to be dried is grinded and ground under dry conditions and passed through a 60-mesh sieve. 13, after the deployment of batch-level tests, according to the provisions of the rational allocation of different grades of products.