INRA, UR370 Qualité des Produits Animaux, F-63122 Saint Genès-Champanelle, France.
INRA, UR370 Qualité des Produits Animaux, F-63122 Saint Genès-Champanelle, France.
Food Chem. 2018 Mar 15;243:295-304. doi: 10.1016/j.foodchem.2017.09.135. Epub 2017 Sep 28.
The chemical changes (oxidation/nitrosation) of meat proteins during digestion lead to a decrease in their nutritional value. Moreover, oxidized and nitrosated amino acids are suspected to promote various human pathologies. To investigate the mechanisms and the kinetics of these endogenous protein modifications, we used a dynamic artificial digestive system (DIDGI®) that mimics the physicochemical conditions of digestion. The combined effect of meat cooking and endogenous addition of ascorbate and nitrite was evaluated on protein oxidation (by measuring carbonyl groups), protein nitrosation (by measuring nitrosamines), and proteolysis. Considerable carbonylation was observed in the digestive tract, especially under the acidic conditions of the stomach. Nitrosamines, caused by ammonia oxidation, were formed in conditions in which no nitrite was added, although the addition of nitrite in the model significantly increased their levels. Meat cooking and nitrite addition significantly decreased protein digestion. The interactions between all the changes affecting the proteins are discussed.
在消化过程中，肉蛋白的化学变化（氧化/亚硝化）会导致其营养价值降低。此外，氧化和亚硝化的氨基酸被怀疑会促进各种人类疾病。为了研究这些内源性蛋白质修饰的机制和动力学，我们使用了一种动态人工消化系统（DIDGI®），该系统模拟了消化的物理化学条件。评估了肉的烹饪和内源性添加抗坏血酸和亚硝酸盐对蛋白质氧化（通过测量羰基）、蛋白质亚硝化（通过测量亚硝胺）和蛋白水解的综合影响。在消化道中观察到大量的羰基化，特别是在胃的酸性条件下。在没有添加亚硝酸盐的情况下，由氨氧化引起的亚硝胺形成，尽管在模型中添加亚硝酸盐会显著增加它们的水平。肉的烹饪和亚硝酸盐的添加显著降低了蛋白质的消化。讨论了所有影响蛋白质的变化之间的相互作用。
