Wang Jing, Aalaei Kataneh, Skibsted Leif H, Ahrné Lilia M
Department of Food Science, University of Copenhagen, 1958 Frederiksberg C, Denmark.
Foods. 2020 Dec 16;9(12):1873. doi: 10.3390/foods9121873.
Yogurt-based snacks originally with a calcium content between 0.10 and 0.17 mmol/g dry matter were enriched with a whey mineral concentrate and whey protein isolate or hydrolysate. Whey mineral concentrate was added to increase the total amount of calcium by 0.030 mmol/g dry matter. Calcium bioaccessibility was determined following an in vitro protocol including oral, gastric, and intestinal digestion, with special focus on the effect of lime juice quantifying calcium concentration and activity. Calcium bioaccessibility, defined as soluble calcium divided by total calcium after intestinal digestion amounted to between 17 and 25% for snacks without lime juice. For snacks with lime juice, the bioaccessibility increased to between 24 and 40%, an effect attributed to the presence of citric acid. Citric acid increased the calcium solubility both from whey mineral concentrate and yogurt, and the citrate anion kept supersaturated calcium soluble in the chyme. The binding of calcium in the chyme from snacks with or without lime juice was compared electrochemically, showing that citrate increased the amount of bound calcium but with lower affinity. The results indicated that whey minerals, a waste from cheese production, may be utilized in snacks enhancing calcium bioaccessibility when combined with lime juice.
最初钙含量在0.10至0.17毫摩尔/克干物质之间的酸奶基零食，用乳清矿物质浓缩物和乳清蛋白分离物或水解物进行了强化。添加乳清矿物质浓缩物是为了使钙总量增加0.030毫摩尔/克干物质。按照包括口腔、胃和肠道消化的体外实验方案测定钙生物可及性，特别关注柠檬汁对钙浓度和活性的影响。对于不含柠檬汁的零食，钙生物可及性定义为肠道消化后可溶性钙除以总钙，其范围在17%至25%之间。对于含柠檬汁的零食，生物可及性增加到24%至40%之间，这一效果归因于柠檬酸的存在。柠檬酸增加了来自乳清矿物质浓缩物和酸奶的钙溶解度，并且柠檬酸根阴离子使过饱和钙在食糜中保持可溶。通过电化学方法比较了含或不含柠檬汁的零食在食糜中钙的结合情况，结果表明柠檬酸增加了结合钙的量，但亲和力较低。结果表明，奶酪生产中的废弃物乳清矿物质，与柠檬汁结合时可用于零食中，提高钙生物可及性。
