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PubMed · 8880456

A method for isolating beta-casein.

L S Ward·E D Bastian
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Abstract

A new method was developed for obtaining pure beta-CN. Calcium caseinate (3%) was reconstituted, renneted to form a gel, cooled (4 degrees C) to allow beta-CN dissociation from the caseinate gel, and centrifuged. The supernatant was warmed to 30 degrees C, precipitating pure beta-CN from solution. Large quantities of beta-CN were recovered by scaling-up this procedure, but these beta-CN preparations were less pure than the beta-CN that was prepared on a smaller scale. Chromatography (FPLC) and urea-PAGE showed beta-CN to be the main component in the precipitate. Chymosin, used to form the caseinate gel, did not extensively hydrolyze beta-CN under the conditions of these experiments. Calcium concentration, cooling time, and caseinate concentration influenced the recovery of beta-CN. Maximum recovery of beta-CN, under the experimental conditions used, occurred at 10 mM calcium, 48 h of cooling, and 3% caseinate concentration.

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CalciumCaseinsChemical PrecipitationChromatography, High Pressure LiquidChymosinElectrophoresis, Polyacrylamide GelGelsHydrolysisPeptide FragmentsUreaJournal ArticleResearch Support, Non-U.S. Gov't

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L S Ward, E D Bastian. 1996. A method for isolating beta-casein.. https://doi.org/10.3168/jds.s0022-0302(96)76489-5

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