壳聚糖法提取乳清粉中的β-乳球蛋白

探索壳聚糖法提取乳清粉中β-乳球蛋白的工艺条件，考查影响提取效果的主要因素，通过正交试验优化提取工艺。用聚丙烯酰胺凝胶电泳法(SDS-PAGE)和紫外分光光度法对β-乳球蛋白产品进行定性及定量分析。结果表明，最佳的工艺条件为：络合时pH6.2，壳聚糖的添加量为2mg/ml乳清粉溶液，NaCl浓度为0.4mol/L，解离时pH11。在此条件下，所得最终产品的β-乳球蛋白含量可达95.12%，得率为93.65%。

Use of Chitosan for Isolation of Beta-lactoglobulin from Whey Powder

On the basis of a fact that β-lactoglobulin (β-LG) can be conjugated to chitosan due to electrostatic interactions under acidic pH condition, and deconjugated from the polysaccharides under alkaline pH condition, β -LG was isolated from whey powder by the addition of chitosan. In order to maximize extraction yield, crucial affecting factors of β -LG extraction which were determined by single factor method were optimized using orthogonal array design. Results showed that a final product with a β -LG purity of 95.12% and a yield of 93.65% was obtained through the optimal extraction procedure based on conjugation with the addition of 2 mg of chitosan to 1 ml of whey powder solution at pH 6.2, followed by deconjugation in 0.4 mol/L NaCl solution at pH 11.