Abstract: A packaged aseptic soybean curd is produced by sterilizing a soybean milk and bittern separately by heating, and by cooling the sterilized soybean milk and bittern separately to below the coagulation temperature of the soybean milk. The cooled soybean milk is passed to a filling device through a main conduit, and the cooled bittern is passed through a subconduit to the main conduit at a position close to the filling device. The bittern and the soybean milk are mixed with the main conduit immediately before being passed to an aseptic chamber where the mixture is placed in a container made of a material which serves a barrier to gases. The filled container is closed with a closure which is also made of a material which serves as a barrier to gases and sealed in the same. The sealed container is then heated to coagulate the mixture therein and obtain a soybean curd.