Acid Phosphates and Phosphatic Fertilizers," 2nd. ed., pp. 372-4, Reinhold, New York, 1952.

Castor beans contain a powerful allergenic protein fraction which severely limits the usefulness of the meal after oil extraction. The solvent-extracted meal or pomace cannot be handled safely by people subject to allergic sensitization. The allergen can be destroyed by treatment with lime. A factorial experiment under pilot plant conditions was

Castor oil is a useful chemical raw material, but the pomace remaining after its extraction is potentially toxic and allergenic. Improving the economic value of castor pomace will provide considerable incentive for increased production of castor seed in the United States. Processes for detoxifying and deallergenating castor meal have been developed along with means for evaluating these processes. Castor meal may be used as a feed supplement for both ruminant and nonruminant animals.

A series of pilot plant batches of castor meal have been prepared using steam as the deactivating medium. Treatments consisted of 12 combinations of 10, 20, 40 and 80 psig steam pressure for i -,, 30 and 60 min each. A multiple regression equation derived from the above data relates the guinea pig response to the process variables. This equation is also presented as a two-dimensional surface contour. The antigenicity levels of untreated castor meals were found to be significantly different. This difference was not retained after treatment. Because of the uncertainty of the antigenicity of the pomace before treatment, an alcohol extract from castor beans (CBWU) has been adopted as a standard for potency evaluations. Amino acid analyses were performed on selected treatments. Considerable antigen deactivation has been achieved using mild steam treatments, e.g., 10 psig for 60 min. This process has a mild effect upon the essential amino acid, lysine.

This is one paper of a series reporting on processes to deactivate the castor antigens. This report gives an analysis of ammonia process variables affecting antigenicity responses. The degree of destruction of antigen obtained by treatment with ammonia under relatively mild conditions of heat is comparable to that obtained with high pressure steam.