An improved process for preparing dry particulate bodies containing a solid peroxyacid compound is disclosed, comprising the steps of
(A) forming a water-wet mixture of a solid peroxyacid compound and a hydratable material having a temperature of hydration of up to 40° C, at a temperature which is higher than the temperature of hydration of the hydratable material; (B) forming the mixture of (A) into particles of the desired shape and size before, during or after cooling the mass to below the temperature of hydration of the hydratable material; and (C) drying the particles obtained from step (B), the improvement being that in step (A) a film-forming material is incorporated in, and intimately mixed with, the water-wet mixture, forming a mix having a pH of below 7. The peroxyacid-containing bodies obtainable therefrom are extremely suitable for use as a bleach additive and for the incorporation in bleaching and/or detergent powder compositions.