Analytica Laboratories Ltd., Ruakura Research Centre, 10 Bisley Rd, Hamilton 3240, New Zealand.
J Agric Food Chem. 2020 Apr 8;68(14):4261-4267. doi: 10.1021/acs.jafc.9b06965. Epub 2020 Mar 24.
New Zealand manuka honeys are known for their propensity to increase apparent C4 sugar content during storage. Depending on the particular storage regime and the initial content of dihydroxyacetone (DHA) in honey, the ready-to-market product often fails the C4 sugar test because of the above phenomenon. We have used DHA labeled with a radioactive C isotope in a set of honeys subject to an incubation experiment. These honeys were analyzed for DHA, methylglyoxal (MG), hydroxymethylfurfural (HMF), apparent C4 sugars, and C scintillation counts over a period of 18 months. The major conclusion of this experiment is that neither DHA nor MG is responsible for the δC shift in the honey protein extract. There must be some other yet unknown substance of manuka honey, which binds to the protein and causes negative δC shift. One identified candidate for such a binding is carbon dioxide.
新西兰麦卢卡蜂蜜以其在储存过程中增加表观 C4 糖含量的倾向而闻名。根据特定的储存条件和蜂蜜中二羟丙酮 (DHA) 的初始含量，由于上述现象，即将上市的产品往往无法通过 C4 糖测试。我们在一组接受孵育实验的蜂蜜中使用放射性 C 同位素标记的 DHA。在 18 个月的时间里，对这些蜂蜜进行了 DHA、甲基乙二醛 (MG)、羟甲基糠醛 (HMF)、表观 C4 糖和 C 闪烁计数分析。该实验的主要结论是，DHA 和 MG 都不是蜂蜜蛋白提取物中 δC 偏移的原因。麦卢卡蜂蜜中一定还有某种其他未知物质与蛋白质结合，导致负的 δC 偏移。二氧化碳是这种结合的一个已确定的候选物质。
