咖啡豆中基酸与氨酸形成的氨酸吸附体
Sorel Tchewonpi Sagu1, Nina Ulbrich2,3, Johanna Rebekka Morche2
1Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 2, 06120 Halle (Saale), Germany.
Foods (Basel, Switzerland)
|June 19, 2024
概括
这项研究确定了绿色咖啡豆中的氨酸-酸 (CQA) 添加物,揭示了对咖啡豆化学的新见解. 这些添加物没有在烤豆中发现,这表明加工影响了它们的形成.
科学领域:
- 食品化学 食品化学
- 分析化学 分析化学
- 生物化学 生物化学
背景情况:
- 咖啡豆的收获后加工涉及复杂的蛋白质反应.
- 蛋白质和化合物之间的交叉连接,如基酸 (CQAs),是咖啡化学的一个具有挑战性的领域.
研究的目的:
- 为了评估咖啡样本中氨酸-氨酸 (CQA) 添加物的存在.
- 通过模型系统研究这些添加物的形成和稳定性.
主要方法:
- 绿色和烤咖啡豆 (阿拉伯咖啡,Canephora,Liberica) 的特征.
- 开发有针对性的液体染色体质谱法 (LC-MS/MS) 方法.
- 模型实验使用CQAs的氨酸,氨酸和N-氨酸氨酸.
主要成果:
- 半氨酸通过 thiol 组与 CQA 结合,形成六种不同的 Cys-CQA 添加物 (m/z 476).
- 在pH值为9的条件下, adduct形成是有利的,而 adducts在高达90°C和28天内是稳定的.
- 在绿色咖啡豆中量化了Cys-CQA添加物 (峰值面积1100-3000),但在烤咖啡豆中没有检测到.
结论:
- 这项研究提供了第一份关于咖啡豆中Cys-CQA添加物的证据.
- 这一发现为进一步研究咖啡中蛋白质水平上的 adduct 形成铺平了道路.
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