SUMMARY— Under optimum conditions Acid Orange–12 will bind to the proteins of meat and eggs. The dye-binding capacity is somewhat greater for these products than the previously reported values for wheat and milk products. A standard curve relating free dye concentration to mg of protein in the sample as determined by the Kjeldahl method can be readily prepared for each type of product. The method is rapid and useful for composition control in ground meats, eggs and prepared mixes. Cooking has little effect on the dye-binding capacity but hydrolysis of the proteins to the proteose-peptone stage reduces the dye bound. The coefficient of variation averaged about 3% of the protein content for the samples of meat and eggs tested.