Pure milk can be heated, but the temperature can not be too high, at about 40 ℃ can be. Lower temperature pure milk can stimulate the stomach, causing gastrointestinal discomfort, but the heating temperature of pure milk is too high can cause protein denaturation, containing phosphoric acid composition precipitation, taste reduction, and cause vitamin C, trace elements and other nutrients loss. When the heating temperature exceeds 100 ℃, lactose will be degraded to produce lactic acid, acetic acid, formic acid and so on. You can soak packaged pure milk in warm water at about 50 degrees for 5 to 10 minutes. Pour the pure milk into a pot and cook it over a slow fire until the surface is bubbling and hot. Microwave heating of milk is not highly recommended. Microwave heating is unevenly distributed between hot and cold, which can easily lead to high temperature of some milk and reduce its nutritional value.