Color predominante de la superficie de los tubérculos
| Code | Term | Description |
|---|---|---|
| 1 | Blanco amarillento (4D) | |
| 2 | Amarillo claro (9D; 10C; 12C) | |
| 3 | Amarillo intenso (13B, C; 15C, D) | |
| 4 | Amarillo naranja (14C; 16B; 20A, B; 22B; 23B; 24B) | |
| 5 | Rojo grisáceo (180A-C) | |
| 6 | Rojo grisáceo intenso (178A-C) | |
| 7 | Marrón (200D, C) | |
| 8 | Púrpura grisáceo (187C, D) | |
| 9 | Negro (200A) |