A refinery is a processing facility that removes impurities from raw materials, and in the food world the term most often means a sugar refinery or an edible-oil refinery. A sugar refinery takes raw cane sugar and purifies it through washing, dissolution, filtration, decolourisation, and recrystallisation into white sugar. An oil refinery degums, neutralises, bleaches, and deodorises crude vegetable oils, removing free fatty acids, pigments, and off-flavours to produce a stable, neutral oil. Both are large-scale continuous operations where yield, energy use, and effluent control decide profitability. Refining improves keeping quality and consistency but also removes minor components, which is why unrefined sugars and cold-pressed oils are marketed on the character that refining takes away.