Releasing oil is an oil applied to bakeware to stop food sticking during cooking. Brushed or sprayed onto tins, trays, and moulds before the batter or dough goes in, it forms a thin barrier between the food and the metal so cakes, breads, and pastries turn out cleanly with their crusts intact. Neutral-flavoured vegetable oils are the usual choice, sometimes combined with flour dusting for extra insurance, while butter adds flavour where it suits the recipe. Commercial bakeries use aerosol release sprays with lecithin for speed and even coverage. The principle is simple but the execution matters: too little oil and the bake welds itself to the tin, too much and the base fries greasy. Proper releasing keeps both product and pans in good condition.