Data_Sheet_1_Circulating Branched Chain Amino Acid Concentrations Are Higher in Dairy-Avoiding Females Following an Equal Volume of Sheep Milk Relative to Cow Milk: A Randomized Controlled Trial.docx

Background: Intolerances to bovine dairy are a motivating factor in consumers seeking alternate—or replacement—dairy beverages and foods. Sheep milk (SM) is an alternate dairy source, with greater protein, although similar amino acid composition compared to cow milk (CM). Studies are yet to address the appearance of circulating amino acids following consumption of SM, relative to CM, in humans.Objective: To clinically determine the appearance of branched chain amino acids, and other amino acids, in circulation in response to equal servings of SM and CM, in females who avoid dairy products.Design: In a double-blinded, randomized, cross-over trial, 30 self-described dairy avoiding females (20–40 years) drank 650 mL of SM or CM that were reconstituted from the spray dried powders (30 and 25 g in 180 mL water, respectively) on separate occasions, following an overnight fast. After reconstitution, the energy and protein provided by SM was higher than for CM (2,140 vs. 1,649 kJ; 29.9 vs. 19.4 g protein); content of branched chain amino acids (BCAAs) were 10.5 and 6.5 mg·mL−1, respectively. Blood samples were collected at fasting and at regular intervals over 5 h after milk consumption. Plasma amino acids were measured by HPLC.Results: 80% of subjects self-identified as lactose intolerant, and the majority (47%) “avoided drinking milk” “most of the time”. SM resulted in greater plasma appearance of BCAAs at 60 min (641.1 ± 16.3 vs. 563.5 ± 14.4 μmol·L−1; p < 0.001) compared with CM. SM similarly resulted in elevated postprandial concentrations of the amino acids lysine, methionine, and proline, particularly at 240 min (time × milk interactions p = 0.011, 0.017, and p = 0.002, respectively). Postprandial increases in plasma alanine concentrations were sustained to 120 min after CM (time × milk interaction p = 0.001) but not after SM, despite greater quantities provided by SM.Conclusions: SM is a rich source of protein, and relative to CM, provides a greater quantity of BCAAs, with a corresponding elevation of the postprandial circulating BCAA response. SM is therefore a possible dairy alternative of benefit to those who need to increase total protein intake or for individuals with heightened protein requirements.Unique Identifier and Registry: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375324, identifier U1111-1209-7768

背景：乳牛乳制品的不耐受性是消费者寻求替代或替代乳制品及食品的驱动因素。羊乳（SM）作为一种替代乳制品来源，其蛋白质含量更高，尽管与牛乳（CM）相比，其氨基酸组成相似。目前尚无研究探讨人类在摄入SM后相对于CM，循环氨基酸出现的状况。目标：在临床层面上确定，在避免乳制品的20至40岁女性中，饮用等量的SM和CM后，血液循环中支链氨基酸以及其他氨基酸的出现情况。设计：在一项双盲、随机、交叉试验中，30名自述避免乳制品的女性（20-40岁）分别在空腹状态下，于不同时间点饮用由喷雾干燥粉末（SM为30克，CM为25克，均溶解于180毫升水中）制成的650毫升SM或CM。SM提供的能量和蛋白质含量高于CM（2,140与1,649千焦；29.9与19.4克蛋白质）；支链氨基酸（BCAAs）含量分别为10.5和6.5毫克·毫升-1。在饮用牛奶后5小时内，每隔一定时间收集血液样本。通过高效液相色谱法（HPLC）测定血浆氨基酸。结果：80%的受试者自认为乳糖不耐受，其中多数（47%）“大部分时间避免饮用牛奶”。与CM相比，SM在60分钟时导致血浆BCAAs出现量显著增加（641.1 ± 16.3与563.5 ± 14.4微摩尔·升-1；p < 0.001）。SM同样导致赖氨酸、蛋氨酸和脯氨酸等氨基酸的餐后浓度升高，特别是在240分钟时（时间与牛奶交互作用p = 0.011，0.017和p = 0.002，分别）。尽管SM提供的数量更多，但CM餐后血浆丙氨酸浓度在120分钟后持续增加（时间与牛奶交互作用p = 0.001），而SM则没有。结论：SM是蛋白质的丰富来源，相对于CM，SM能提供更多的BCAAs，从而引起餐后循环BCAA反应的相应升高。因此，SM对于需要增加总蛋白质摄入量的人群或蛋白质需求增加的个体而言，是一种可能的乳制品替代品。唯一标识符和注册信息：https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375324，标识符U1111-1209-7768