Department of Food Science, Faculty of Science , University of Copenhagen , Rolighedsvej 26 , 1958 Frederiksberg C , Denmark.
Department of Biomedical Sciences, Faculty of Health and Medical Sciences , University of Copenhagen , Blegdamsvej 3 , 2200 Copenhagen N , Denmark.
J Agric Food Chem. 2019 Jun 5;67(22):6350-6358. doi: 10.1021/acs.jafc.9b01532. Epub 2019 May 22.
α-Dicarbonyls are reactive intermediates formed during Maillard reactions and carbohydrate degradation. The formation of seven α-dicarbonyls was characterized in solutions containing dairy related carbohydrates (galactose, glucose, lactose, and galacto-oligosaccharides (GOS)) during incubations at 40 and 50 °C with and without Nα-acetyl-l-lysine at pH 6.8 for up to 2 months. The concentrations of α-dicarbonyls in samples of monosaccharides with Nα-acetyl-l-lysine were found to be 3-deoxyglucosone (3-DG) > 3-deoxygalactosone (3-DGal) > glyoxal > glucosone, galactosone > methylglyoxal > diacetyl. The presence of Nα-acetyl-l-lysine resulted in up to 100-fold higher concentrations of C6 α-dicarbonyls but lesser formation of glyoxal in the monosaccharide-containing models compared to what was observed in the absence of Nα-acetyl-l-lysine. Galactose incubated with Nα-acetyl-l-lysine generated the highest concentrations of 3-DGal (up to 130 μM), glyoxal (up to 100 μM), and methylglyoxal (up to 9 μM) compared to the other carbohydrates during incubation. Surprisingly, 3-DG (1500 μM) and 3-DGal (80 μM) were formed at levels of 2 orders of magnitude higher in solutions of GOS in the absence of Nα-acetyl-l-lysine as compared to the other carbohydrates at 40 °C, while GOS generated the lowest levels of glyoxal. GOS are widely used as an ingredient in various types of foods products, and it is therefore of importance to consider the risk of generating high levels of the reactive C6 α-dicarbonyl, 3-DG, in these types of products. This study contributes to the understanding of major α-dicarbonyl formation as affected by the presence of primary amines in GOS-, lactose-, and galactose-containing solutions under moderate heating in liquid foods.
α-二羰基化合物是美拉德反应和碳水化合物降解过程中形成的反应中间体。在 pH 值为 6.8 时，将与乳相关的碳水化合物（半乳糖、葡萄糖、乳糖和半乳糖寡糖（GOS））在 40 和 50°C 下孵育，并在有无 Nα-乙酰-L-赖氨酸的情况下，研究了七种α-二羰基化合物的形成。在含有 Nα-乙酰-L-赖氨酸的单糖样品中，发现α-二羰基化合物的浓度为 3-脱氧葡萄糖酮（3-DG）>3-脱氧半乳糖酮（3-DGal）>乙二醛>葡萄糖酮，半乳糖酮>甲基乙二醛>双乙酰。与没有 Nα-乙酰-L-赖氨酸的情况相比，存在 Nα-乙酰-L-赖氨酸会导致 C6α-二羰基化合物的浓度增加 100 倍，但在含有单糖的模型中，乙二醛的形成较少。与其他碳水化合物相比，用 Nα-乙酰-L-赖氨酸孵育的半乳糖生成的 3-DGal（高达 130 μM）、乙二醛（高达 100 μM）和甲基乙二醛（高达 9 μM）的浓度最高。令人惊讶的是，在没有 Nα-乙酰-L-赖氨酸的情况下，与其他碳水化合物相比，GOS 溶液中 3-DG（高达 1500 μM）和 3-DGal（高达 80 μM）的形成水平高 2 个数量级，而 GOS 生成的乙二醛水平最低。GOS 广泛用作各种类型食品的成分，因此，在这些类型的产品中，需要考虑生成高水平的反应性 C6α-二羰基化合物 3-DG 的风险。本研究有助于理解在液体食品中适度加热时，GOS、乳糖和半乳糖溶液中存在伯胺对主要α-二羰基化合物形成的影响。
Zotero 插件