Fuente: WIPO "milk" [Problems] To provide a container not deformed nor burst even if its content and gas in the container inflate due to a temperature difference between before and after forming a frozen material packaging body and also capable of performing hygienic administration of the content. [Means for Solving Problems] A vent port covered with a filter material having microbial impermeability and air permeability is formed at least in a portion of the container.