α-Lactalbumin bound with negligible, one and two Ca ions (, -Ca and -2Ca La) were prepared, and thermal stability and gastrointestinal digestibility under infant, adult and elderly conditions were studied. -2Ca La was prepared by adding 1.5 mol Ca mol La to -Ca La solution. Almost complete release of bound Ca from -Ca La was achieved at pH 2.0. Bound Ca was limitedly released from -Ca La using citrate, and was readily released using EDTA especially at alkaline pH. La was prepared by 5 stages of 4× ultrafiltration of -Ca La solution with 8 mol added EDTA mol La at pH 8.0, where the bound Ca ion remained at 0.03 mol mol La. Thermal stability increased in order of -Ca and -2Ca La. Infant gastrointestinal digestibility increased in order of -2Ca, -Ca and La. Digestibility of La increased in order of infant, elderly and adult conditions.

中文翻译：

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钙结合影响婴儿、成人和老年人条件下牛 α-乳清蛋白的体外胃肠道消化

制备了与可忽略不计的 1 个和 2 个 Ca 离子（-Ca 和 -2Ca La）结合的 α-乳清蛋白，并研究了婴儿、成人和老年人条件下的热稳定性和胃肠道消化率。 -2Ca La 是通过将 1.5 mol Ca mol La 添加到 -Ca La 溶液中制备的。在 pH 2.0 时，几乎完全从 -Ca La 中释放出结合的 Ca。使用柠檬酸盐，结合的 Ca 可以从 -Ca La 中有限地释放，并且使用 EDTA 可以很容易地释放，特别是在碱性 pH 下。 La是通过在pH 8.0下添加8 mol EDTA mol La的-Ca La溶液经过5级4×超滤制备的，其中结合的Ca离子保持在0.03 mol mol La。热稳定性按-Ca和-2Ca La的顺序增加婴儿胃肠道消化率按-2Ca、-Ca、La的顺序增加。La的消化率按婴儿、老年人、成人的顺序增加。