Nutritional Value of Mustard and Rape Seed Meals as Protein Source for Rats

Mustard seed meal has been successfully treated to remove the sharp flavor, producing a very bland material. This meal appeared to be a satisfactory protein source for rats as no toxic factors were in evidence even when this material was used as a sole protein source for two generations. This protein is high in lysine, methionine, threonine and tryptophan. Being to some degree deficient in valine it was most satisfactory when blended with proteins containing adequate amounts of this amino acid. A 50% blend of mustard and soybean meal gave equal gains and better feed efficiency than straight soybean meal. Rape seed meal is quite inferior to mustard meal as a protein source. Enzyme treatment improved rape seed meal but the toxic factors appeared to concentrate in the liquid from the enzyme treatment. By discarding this fraction it might be possible to produce a satisfactory protein especially when blended with other protein sources. Experiments are now under way to test this thesis.