A method of treating food capable of easily softening or pulverizing food in a short time without losing nutrients is provided. A shock wave (SW) generated in a shock wave source is applied to food such as an apple or tea leaves to soften or pulverize the food. A large mechanical load is not necessary, so the food is easily softened or pulverized. Moreover, it is not necessary to heat the food, so the food is softened or pulverized in a short time without losing nutrients in the food due to heat during heating.