Coprecipitation of acid cheese whey and tannery waste and recovery of protein

Combining acid cottage cheese whey and the lime–sulfide effluent from tannery unhairing processes spontaneously coprecipitates the whey proteins with the large peptides and proteins of the tannery waste. The floculation of the denatured protein material also carries down the hide pigments, excess lime, and the casein fines from the whey. The clear supernatant contains lactose, sulfur in various states of oxidation, free amino acids, peptides, and ammonium salts, but no detectable macromolecular proteins. The recovered solid products, which contain more than 20% of the original nitrogen, appear to have a good balance of essential amino acids although actual composition varies with the composition of the raw wastes. Feed supplements may possibly by obtained by this method from two presently wasted industrial effluents.