But using casserole gives people a feeling of safety and health. Eating casserole stew in winter makes people have an appetite. But casserole dishes should not be eaten often. Because of the long heating time, protein, an animal food raw material, degrades, and the solubility of water is weakened, and a large amount of gelatinous liquid is precipitated, which increases its toughness and makes its taste worse, which is not conducive to human digestion and absorption. Moreover, the loss rate of minerals and vitamins in raw materials during casserole stew is high. In addition, due to strict sealing, it is difficult for the odor substances in the raw materials to escape, and there are still some valeric acid and low fat in the raw materials and soup materials, which will generate substances harmful to human body in the thermal reaction. So use it less.