Meija Juris, Bryson Joshua M, Vonderheide Anne P, Montes-Bayón Maria, Caruso Joseph A
Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, USA.
J Agric Food Chem. 2003 Aug 13;51(17):5116-22. doi: 10.1021/jf034210h.
Coffee has been an important and heavily used beverage in many cultures over a long period of time. Although sulfur species have been found to be abundant constituents, no work to date has explored the presence of selenium analogues. Investigation of volatile selenium species from green coffee beans, roasted beans, and brewed coffee drink was performed using solid phase microextraction (SPME) sample preconcentration in conjunction with GC/ICP-MS. Several volatile selenium species at trace levels were detected from roasted coffee beans as well as in the steam from brewed coffee drinks. No detectable selenium (and sulfur) species, however, were found in the headspace of green beans, indicating that selenium-containing volatiles are formed during roasting, as is the case for the sulfur volatiles. Matching standards were prepared and used to identify the compounds found in coffee. Artificial supplementation of the green coffee beans with selenium before roasting was performed to further characterize the selenium-containing volatiles formed during the coffee-roasting process.
长期以来,咖啡在许多文化中一直是一种重要且被大量饮用的饮品。尽管已发现含硫物质是其丰富成分,但迄今为止尚无研究探索硒类似物的存在情况。采用固相微萃取(SPME)样品预浓缩结合气相色谱/电感耦合等离子体质谱(GC/ICP-MS)对生咖啡豆、烘焙咖啡豆和煮制咖啡饮品中的挥发性硒物种进行了研究。从烘焙咖啡豆以及煮制咖啡饮品的蒸汽中检测到了几种痕量的挥发性硒物种。然而,在生咖啡豆的顶空中未检测到可检测的硒(和硫)物种,这表明含硒挥发物是在烘焙过程中形成的,硫挥发物的情况也是如此。制备了匹配标准物并用于鉴定咖啡中发现的化合物。在烘焙前对生咖啡豆进行人工硒补充,以进一步表征咖啡烘焙过程中形成的含硒挥发物。