The definitions of tomato purée vary between regions. In the USA, tomato purée is a processed food product, usually consisting of only tomatoes, but can also be found in pre-seasoned form. It differs from tomato sauce or tomato paste in consistency and content; tomato puree generally lacks the additives common to a complete tomato sauce, and does not have the thickness of paste. To prepare tomato purée, ripe tomatoes are washed and the leaves and stem are removed. Some processors remove the skin of the tomato as well. This is then mashed or mechanically chopped to the desired consistency.