Bratthäll Tove, Figueira João, Nording Malin L
Department of Chemistry, Umeå University, 901 87, Umeå, Sweden.
Department of Chemistry, SciLife Lab, Umeå University, 901 87, Umeå, Sweden.
Heliyon. 2024 Feb 17;10(5):e26625. doi: 10.1016/j.heliyon.2024.e26625. eCollection 2024 Mar 15.
The perceived flavor of coffee varies depending on the composition of the brewing water, and the influencing mechanisms are poorly understood. To investigate the effect of dissolved divalent cations on the extraction of organic acids in coffee, magnesium and calcium chloride salts were added pre- and post-brew. Citric, malic, lactic and quinic acid were analyzed using gas chromatography - mass spectrometry and nuclear magnetic resonance techniques. At concentrations typically found in drinking water, the salts resulted in limited variation of the acid content, while ten-fold higher salt concentrations produced more pronounced variations. Comparisons between pre- and post-brew additions showed similar acid content in most cases, suggesting that extraction of acids proceeds independent of the water composition. Interactions taking place post-brew may, however, influence the perceived flavor. A scientific basis for water quality recommendations in the coffee industry is long overdue and this work provides experimental and analytical contributions to continued research.
咖啡的感知风味因冲泡用水的成分而异，但其影响机制尚不清楚。为了研究溶解的二价阳离子对咖啡中有机酸萃取的影响，在冲泡前和冲泡后添加了镁盐和氯化钙盐。使用气相色谱 - 质谱联用和核磁共振技术分析了柠檬酸、苹果酸、乳酸和奎尼酸。在饮用水中常见的浓度下，这些盐导致酸含量变化有限，而盐浓度高出十倍时则产生更明显的变化。冲泡前和冲泡后添加盐的比较表明，在大多数情况下酸含量相似，这表明酸的萃取过程与水的成分无关。然而，冲泡后发生的相互作用可能会影响感知风味。咖啡行业早就应该有水质推荐的科学依据了，这项工作为持续研究提供了实验和分析方面的贡献。
