Water that has been made slightly acidic by the addition of an acid substance such as lemon juice or vinegar (about one teaspoon to half a litre of water). Peeled fruit and vegetables such as apples, pears, celeriac, globe artichokes and salsify are immersed in acidulated water to prevent them from discolouring. It can also be used for cooking. Cauliflower, for instance, will be snowy white if boiled in acidulated water.