Nutritional and metabolic consequences of the early Maillard reaction of heat treated milk in the pig.: Significance for man
Nutritional and metabolic consequences of the early Maillard reaction of heat treated milk in the pig.: Significance for man
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DOI：
10.1007/s003940200000
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发表时间：
2002-02-01
影响因子：
5
通讯作者：
Finot, PA
中科院分区：
文献类型：
--
作者：
Rérat, A;Calmes, R;Finot, PA
背景在食品加工过程中，美拉德反应可能会发生，从而改变蛋白质的营养价值。在乳制品中，乳果糖赖氨酸的形成降低了赖氨酸的可用性，但对其他营养素的影响还不是很清楚。研究的目的确定牛奶中高水平的乳果糖赖氨酸对脱脂牛奶营养素的生物利用度的影响，以及它们在门静脉血中出现的动力学和它们的尿液和粪便排泄物的动力学，并外推到较低的热处理和人，方法亚成年猪在麻醉状态下，在门静脉、颈动脉和尿道中安装永久性导管，并在门静脉周围安装电磁流量探头。每只动物连续喂食两份实验餐，其中含有等量的脱脂奶粉（SM），经冻干或热处理以获得强烈的美拉德反应（M-SM），导致50%的赖氨酸阻断。门静脉和动脉的浓度和流量的个别氨基酸（AA），葡萄糖，半乳糖和果糖赖氨酸进行了测量，一段时间的12小时后的饭菜。结果在含50%封闭赖氨酸的M-SM中，AA未被化学修饰。果糖赖氨酸出现在门静脉血中非常晚的氨基酸相比，从一个非常缓慢的释放，并对应于8.2%和18.6%的摄入量后12和72小时，分别。仅观察到门静脉血中赖氨酸（-60%）、丙氨酸（-17%）和胱氨酸（+37%）的外观发生显著变化。在此期间，大部分氨基酸的消化率略有下降，其中赖氨酸、苯丙氨酸、胱氨酸、天冬氨酸、甘氨酸和总氨基酸的消化率在48 h后下降最明显（-6%）。蛋白质营养价值的损失主要是由于赖氨酸的变质，在较小程度上，一些必需氨基酸的消化率下降。考虑到所研究的M-SM样品中乳果糖赖氨酸的水平非常高，可以得出结论，在含有较低水平的封闭赖氨酸的常见食物中，例如牛奶、婴儿配方奶粉、饼干、面包、意大利面，营养损失主要是由于赖氨酸的损失，并且在较小程度上是由于其他必需AA的消化率降低。
Background During the processing of foods, the Maillard reaction may occur contributing to altering the nutritional value of proteins. In dairy products the formation of lactuloselysine reduces the availability of lysine but the effects on the other nutrients are not very well known.Aim of the study Determination of the consequences of a high level of lactuloselysine in milk on the bioavailability of skim milk nutrients and the kinetics of their appearance in the portal blood and of their urinary and faecal excretions and extrapolation to lower heat treatments and to man, using the pig model.Methods Sub-adult pigs were fitted, under anaesthesia, with permanent catheters in the portal vein, carotid artery and urethra, and with an electromagnetic flow probe around the portal vein. Each animal was successively fed with two experimental meals containing an equal amount of dried skim milk (SM), either lyophilised or heat treated to obtain an intense Maillard reaction, (M-SM) resulting in a 50% lysine blockage. Portal and arterial concentrations and flux of individual amino acids (AA), glucose, galactose and fructoselysine were measured for a period of 12h after the meals. Lysine, fructoselysine and AA excreted in the urine and faeces within 72h were also determined.Results In M-SM containing 50% blocked lysine, no other AA was chemically modified. Fructoselysine appeared in the portal blood very late compared to amino acids resulting from a very slow release and corresponded to 8.2 and 18.6% of the ingested amount after 12 and 72h, respectively. Significant changes of the appearance in the portal blood were observed only for lysine (-60%), alanine (-17%) and cystine (+37%). A small decrease in the digestibility of most AA during the same period was observed, which was significant after 48h for lysine, phenylalanine, cystine, aspartic acid, glycine and total AA (-6%).Conclusion It was confirmed that lactuloselysine was not bioavailable. The loss in protein nutritive value was mainly due and proportional to the deterioration of lysine and, to a lesser extent, to the decrease in the digestibility of some essential AA. Taking into account the very high level of lactuloselysine in the M-SM sample studied, it may be concluded that in common foods such as milk, infant formulas, biscuits, bread, pasta, containing lower levels of blocked lysine, the nutritional loss is primarily due to the loss of lysine and to a less extent to the decrease in the digestibility of other essential AA.