Oil cake is the solid portion left after extraction of oil. The oil cakes are of two types: edible oil cakes which can be safely fed to livestock; e.g.: groundnut cake, coconut cake etc., and non-edible oil cakes which are not fit for feeding livestock; e.g.: castor cake, neem cake, mahua cake etc..
Both edible and non-edible oil cakes can be used as manures. However, edible oil cakes are fed to cattle and non-edible oil cakes are used as manures especially for horticultural crops.
Nutrients present in oil cakes, after mineralization, are made available to crops 7 to 10 days after application. Oilcakes need to be well powdered before application for even distribution and quicker decomposition.