PURPOSE: To obtain a product having less variations in the number of solid materials by mixing the solid materials with a liquid material having a predetermined viscocity so as to have a specific ratio of the solid materials, thereby making preserves and then further mixing the preserves after measuring a fixed amount of the same with a liquid separately measured.

CONSTITUTION: In the case where foodstuffs, in which relatively large-sized fruit cut square is mixed with yogurt and the like, are produced, the title device provides a tank 5 for preserves, which containes a solid/liquid mixture (sarcocarp preserves) 4 having solid materials 2, such as fruit pieces, mixed at a relatively high ratio of about 30 to 70% as a whole with a liquid material 3 having a viscocity of at least about 100cp. Further, the device provides: a measuring instrument 6 for receiving the preserves 4 from the tank 5 to measure and feed them; a liquid tank 8 for storing liquid (a yogurt-based mixture) 7 which is finally mixed with the preserves 4; and a measuring instrument 9 adapted to measure the liquid 7. The preserves 4 and the liquid 7 fed from the measuring instruments 6, 9, respectively, are mixed together by a mixer 11 to prepare a solid/liquid foodstuff 10 to be packed, and the foodstuff thus prepared is packed in a container 12 by a filling nozzle 13.