不同水解度酪蛋白磷酸肽的理化性质和持钙能力比较

Comparative study on the physicochemical characteristics and calcium holding capacities of casein phosphopeptides with different degrees of hydrolysis

中文关键词:  酪蛋白磷酸肽  水解度  理化性质  持钙能力

英文关键词:casein phosphopeptide  degree of hydrolysis  physicochemical characteristic  calcium holding capacity

中文摘要:

      目的 研究不同水解度(degree of hydrolysis, DH)酪蛋白磷酸肽(casein phosphopeptide, CPP)的理化性质和持钙能力。方法 实验室自制得到水解度分别为4.32%~26.76%的CPP样品, 分别测定CPP含量[高效液相色谱法(high performance liquid chromatography, HPLC)和钡-乙醇沉淀法]、等电点不溶物含量、相对分子质量分布和持钙能力。结果 随着水解度的上升, 通过HPLC测定的CPP标志峰的峰面积随之增加, 等电点不溶物含量随之减少, 而通过钡-乙醇沉淀法得到的CPP含量无明显变化, 可将等电点不溶物含量作为评价产品质量的指标; 目前的相对分子质量分布检测方法对不同水解度的CPP样品检测误差较大, 需使用酸溶蛋白含量作为校正系数进行校正后方可使用; 当CPP的质量浓度为0.6~0.8 mg/mL时, 水解度为9.22%和15.06%的CPP的持钙能力效果优于其他水解度的CPP。结论 水解度对酪蛋白磷酸肽的理化性质和持钙能力有明显的影响, 在实际应用时应选用合适的水解度和检测方法。

英文摘要:

      Objective To study the physicochemical characteristics and calcium holding capacities of casein phosphopeptides (CPP) with different degrees of hydrolysis (DH). Methods CPP was prepared by the laboratory with the DH of 4.32%–26.76%, the content of CPP [high performance liquid chromatography (HPLC) and barium-ethanol precipitation method], content of isoelectric insoluble substance, molecular mass distribution and calcium holding capacity were measured. Results With the DH increased, the peak area determined by HPLC and the content of isoelectric insoluble substances of CPP were increased and decreased, respectively, but the content of CPP determined by barium-ethanol precipitation method had not significantly changed, and the content of isoelectric point insoluble matter could be used as an index to evaluate the quality of products; the current relative molecular weight distribution detection method had large detection error for CPP samples with different DH, which could be used after using acid soluble protein content as correction coefficient; when the concentration of CPP was 0.6–0.8 mg/mL, the calcium binding capacities of CPP with the DH value of 9.22% and15.06% were better than that of CPP with other DH. Conclusion The degree of hydrolysis has distinct effects on physicochemical characteristics and calcium holding capacities, and the appropriate degree of hydrolysis and detection method should be choose in practical application.