PURPOSE: To prepare a chilled food of rootcrops having the taste, flavor and color of the fresh rootcrops, and useful as a raw material of boiled foods, by cutting the rootcrops, washing with water, immersing in an aqueous solution of an edible organic acid, boiling in water, quenching, vacuum packaging, and again boiling in water.

CONSTITUTION: Rootcrops such as potato, burdock, etc. are skinned, cut, washed with water, immersed in an aqueous solution of e.g. acetic acid, lactic acid, etc., boiled at ≥95°C for 5W10min, quenched, vacuum-packed with a heat-resistant plastic bag, boiled again at 95°C for about 5min, and quenched to obtain the objective product.