PROBLEM TO BE SOLVED: To produce a processed product of a stipe of Undaria pinnatifida Suringar removed from the epidermis, a new food using the processed product of the stipe of the Undaria pinnatifida Suringar and to provide a method for producing the processed product and the new food. SOLUTION: A stipe of Undaria pinnatifida Suringar is subjected to removal of salt and then boiled in hot water containing a vinegar added thereto. After the boiling in hot water, the epidermis is rubbed off and the contents after removing the epidermis are further boiled in hot water in a pressure cooker. After the boiling in hot water, the taken out processed stipe of the Undaria pinnatifida Suringar in the form of Tokoroten (vermicelli-like strips of gelatin made from seaweed) is then converted into a pasty state. A mixture of agar with a granulated sugar and powdery Undaria pinnatifida Suringar is placed in a stock of a sea tangle, boiled and dissolved therein. The pasty processed stipe of the Undaria pinnatifida Suringar and a soybean milk are then added to the resultant solution and the prepared mixture xs formed.
