Alkaline electro-activation of whey was previously reported to convert 25–45% of lactose into lactulose. Neutralization after electro-activation did not cause the loss of the lactulose yield. Lactulose is an established prebiotic and is used as an additive in fermented dairy products. The aim of this work was to study the behavior of electro-activated whey used as an ingredient in a fermented milk. To carry out this study, prior to fermentation, milk (0, 1, 2, and 3% fat) was supplemented with 3, 6, and 9% electro-activated whey. Different analyses were performed such as acidification kinetic, textural, rheological, syneresis, organic acids production, sensorial, and microbiological parameters were assessed. Furthermore, the effect of electro-activated whey on the fermented milk microstructure was analyzed by scanning electron microscopy. The obtained results showed that the addition of electro-activated whey prolonged the time of fermentation. Samples with electro-activated whey had more homogeneous and less porous microstructure and were characterized by a significantly reduced syneresis compared to milk or whey supplemented milk. The presence of electro-activated whey did not hinder bacterial growth and triggered the superior production of organic acids such as lactic, acetic, citric, propionic, and butyric acids. The analysis of residual lactulose during refrigerated storage showed that approximately 50% of lactulose remained in the fermented milk, suggesting that the consumption of such product will provide a sufficient amount of lactulose reaching the host colon. Finally, this study clearly demonstrated the feasibility of using electro-activated whey as a lactulose-containing ingredient in fermented milk manufacturing.

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在发酵乳生产中使用电活化乳清作为原料：技术可行性概念的证明

先前有报道称，乳清的碱性电活化可将 25-45% 的乳糖转化为乳果糖。电活化后的中和不会导致乳果糖产量的损失。乳果糖是一种成熟的益生元，用作发酵乳制品的添加剂。这项工作的目的是研究用作发酵乳成分的电活化乳清的行为。为了进行这项研究，在发酵之前，牛奶（0%、1%、2% 和 3% 脂肪）添加了 3%、6% 和 9% 的电活化乳清。进行了不同的分析，如酸化动力学、质地、流变、脱水收缩、有机酸生产、感官和微生物参数。此外，通过扫描电子显微镜分析了电活化乳清对发酵乳微观结构的影响。所得结果表明，添加电活化乳清延长了发酵时间。与牛奶或添加乳清的牛奶相比，含有电活化乳清的样品具有更均匀且孔隙更少的微观结构，并且其特点是脱水收缩显着降低。电活化乳清的存在不会阻碍细菌生长并引发有机酸如乳酸、乙酸、柠檬酸、丙酸和丁酸的卓越生产。冷藏期间残留乳果糖的分析表明，大约 50% 的乳果糖保留在发酵乳中，表明食用此类产品将提供足够量的乳果糖到达宿主结肠。最后，