The blackening is due to the gelatinization of sugar. So the oil temperature cannot be high. Generally, it is 30% hot, that is, the palm of your hand is placed about five centimeters above the oil level, and you can go to the pot if you don't feel obvious heat. If you feel unsafe, you can even cool the oil before cooking. Keep the fire low until the meatballs float and fry for about one minute. Control the oil in the pot or use a napkin to absorb the oil on the surface.