Individual ovine milk samples were obtained from 2 Corriedal ewes 2 weeks after parturition. The contents of casein, calcium and inorganic phosphorus were 4.46 and 4.86 g, 198.8 and 192.5 mg, and 111.0 and 117.8 mg, respectively, in two 100 mL samples of ovine skim milk. The content of micellar calcium phosphate (MCP)-cross-linked casein in ovine casein micelles, which were determined by high-performance gel permeation chromatography in the presence of 6 M urea, was 57.5% and 58.4% for the two ovine milk samples. The released casein upon cooling at 5℃ for 20 h from casein micelles was 11.2% and 14.4% of total casein in 2 ovine skim milk samples. Most of the released casein from ovine casein micelles upon cooling was β-casein similar to that found in bovine casein micelles. It was considered from the above results that the MCP-cross-linked casein content and behavior of ovine casein micelles were similar to those of bovine casein micelles, although ovine milk was higher in concentrations of casein, calcium and inorganic phosphorus than in bovine milk.

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