A method for processing vegetables comprises (i) a dicing step comprising subjecting the vegetable to mechanical size reduction; (ii) a softening step comprising heating or freezing the vegetable for a pre-determined period; and (iii) a treatment step comprising bringing the softened vegetable product into contact with one or more reactive oxygen species. The reactive oxygen species may be a peroxide, superoxide or ozone. Preferably the method is used for processing cauliflower into a low-carbohydrate substitute for rice. The treatment prevents discolouration and minimises the production of malodorous volatile chemicals.