The present invention relates to a method for the reactive grinding of castor seeds which, using specially processed castor seeds in the presence of a light alcohol and a basic catalyst, enables a grinding and a transesterification reaction of the triglycerides present in the castor oil to be performed in a single step, simultaneously producing an oil cake, glycerol and fatty acid esters, in particular ricinoleic acid. In a straightforward, inexpensive manner, the method for treating castor seeds according to the invention inactivates, in addition to the castor oil, the powerful allergen CB-IA, thus enabling risk-free handling by humans as well as the use of castor oil cakes as animal feed. Characteristically, the grains are processed by a series of operations including a step of flattening and a step of drying said grains.
