Coagulation of protein from aqueous alkaline meat extracts by acidification, heating, and freezing-thawing, was studied between pH 7.0 and 4.5. Protein recovery in excess of 90% was possible by heating momentarily to 80°C or higher at pH 5.0-6.0, but the coagulum was gritty and uncohesive. Lower yields were obtained by mild heating to 6O"C, acid coagulation at pH 5.0 and 5.5, and by rapid freezing to -30°C and thawing of the pH-adjusted extracts. The unheated coagula were cohesive and had good binding properties as determined by texture and sensory tests. Freezing-thawing at pH 6.0 produced a highly structured material. All coagula contained typically 85-87% moisture, lo-12% protein, and less than 0.4% ash. Loss of flavor was the main sensory defect noticed after heating.

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