The basic method of making margarine today consists of emulsifying a blend of oils and fats from vegetable and animal sources, which can be modified using fractionation, interesterification or hydrogenation, with skimmed milk which may be fermented or soured, salt, citric or lactic acid, chilling the mixture to solidify it, and working it to improve the texture. Margarines and vegetable fat spreads found in the market can range from 10% to 90% fat, depending on dietary marketing and purpose (spreading, cooking or baking). The softer tub margarines are made with less hydrogenated and more liquid oils than block margarines.