Department of Chemistry, University of Bath , Claverton Down, Bath, BA2 7AY, U.K.
J Agric Food Chem. 2014 May 28;62(21):4947-50. doi: 10.1021/jf501687c. Epub 2014 May 16.
The flavorsome compounds in coffee beans exist in the form of aprotic charge neutral species, as well as a collection of acids and conjugate salts. The dissolution and extraction of these organic molecules is a process dependent on the dissolved mineral content of the water. It is known that different rates and compositions of coffee extraction are achieved through the control of the water "impurities", Na(+), Mg(2+), and Ca(2+), which coordinate to nucleophilic motifs in coffee. Using density functional theory, we quantify the thermodynamic binding energies of five familiar coffee-contained acids, caffeine, and a representative flavor component, eugenol. From this, we provide insight into the mechanism and ideal mineral composition of water for extraction of flavorsome compounds in coffee.
咖啡豆中的风味化合物以非质子电荷中性物质的形式存在,以及一系列酸和共轭盐。这些有机分子的溶解和提取是一个依赖于水的溶解矿物质含量的过程。众所周知,通过控制水的“杂质”(Na+、Mg2+和 Ca2+)来实现不同速率和组成的咖啡提取,这些杂质与咖啡中的亲核基序配位。使用密度泛函理论,我们定量计算了五种常见的咖啡酸、咖啡因和代表性风味成分丁香酚的热力学结合能。由此,我们深入了解了咖啡中风味化合物提取的机制和理想的水矿物质组成。