Provided is a colored sweet potato which has a high anthocyanin content and is useful as a pigment material. Also provided are a processed product, more specifically an extract composition, of the colored sweet potato which is useful as a purple pigment and a purified product (including a crude purified product) of the same. The colored sweet potato having the following characteristics is used: (A) the color value (530 nm)/g is 15 or higher; (B) the absorbance ratio (320 nm/530 nm)/g is 1.5 or higher; (C) the value: [color value (530 nm)/g]×[absorbance ratio (320 nm/530 nm)/g] is 30 or greater; and (D) Rtsp-1) is inserted into at least two site in the genome sequence and, when a part of a plant body thereof is subjected, as a test material, to a nucleic acid amplification reaction by using primer set 1, said primer set 1 consisting of the base sequence represented by SEQ ID NO:1 and the base sequence represented by SEQ ID NO: 2, and/or primer set 2, said primer set 2 consisting of the base sequence represent
