Baby purée's can be made in a blender, or with special implements such as a potato masher, or by forcing the food through a strainer, or simply by crushing the food in a pot. Purées generally must be cooked, either before or after grinding, in order to improve flavour and texture, remove toxic substances, and reduce their water content.
You can purée entire meals (without use of salt or other additives) to be served to babies as an nutritious meal.