PURPOSE: To simply produce the title food which is an ancient milk product and improve milk product intake of moderns by heating and concentrating a raw milk, allowing the treated raw milk to stand and then collecting the separated and coagulated layer, further heating and concentrating the coagulated material and kneading the concentrated food material up to semi-fluid state.

CONSTITUTION: A raw milk is subjected to primary heating and concentration (preferably at 80-90°C) and the allowed to stand overnight to form a coagulated layer at the upper face and the coagulated layer is separated and collected and then subjected to the secondary heating and concentration (preferably at about 80) and kneaded up to semi-fluid state to provide the aimed SO. Furthermore, the primary heating is carried out until the raw milk is concentrated to amount of about 25-50wt.% of the raw milk and ratio of protein thereof to fat thereof is preferably 1.5-5.6.