The first point: when freezing mung beans and cooking mung bean soup, you must freeze mung beans for more than 6 hours in advance, because the temperature of frozen mung beans is lower than 0 degrees Celsius. When low-temperature mung beans are put into boiling water, they will quickly absorb the heat in the water and expand rapidly. The principle of cooking mung bean soup by freezing method is the well-known physical principle of thermal expansion and cold contraction.

The second point: after boiling for 10 minutes, stew for more than 10 minutes, and then stew for 10 minutes, so as to combine the fragrance and nutrition in mung beans with water and make the mung bean soup more fragrant and refreshing.