van der Stegen G H, Essens P J, van der Lijn J
Sara Lee Douwe Egberts, Vleutensevaart 35, NL-3532 AD Utrecht, The Netherlands.
J Agric Food Chem. 2001 Oct;49(10):4713-5. doi: 10.1021/jf0105586.
A commercial lot of green coffee, naturally contaminated with ochratoxin A (OTA), was roasted under various conditions, and the effects on its final OTA content were determined. Precautions were taken in sampling the coffee to cope with OTA inhomogeneity. The roasting conditions were kept within the range of commercial practice. Roasting time was varied from 2.5 to 10 min, and the roast color varied from light medium to dark. The differences in OTA reduction between the different levels of roasting times and colors did not reach statistical significance. However, for all roasting conditions, the reduction was highly significant, 69% reduction over the combined results. In total, nine studies by various authors about OTA reduction during coffee roasting are now available. Seven out of these nine reported that the relevant range of OTA reductions was between 69 and 96%. Among these seven,are all four studies that reported using naturally contaminated beans, a sampling procedure adapted to mycotoxin inhomogeneity, and roasting conditions within the range of actual practice. Three different explanations are available for this reduction: physical removal of OTA with chaff, isomerization at the C-3 position into another diastereomer, and thermal degradation with possible involvement of moisture. All three explanations may play a partial role in the OTA reduction during coffee roasting.
一批天然受赭曲霉毒素A（OTA）污染的商业生咖啡豆在不同条件下进行烘焙，并测定其对最终OTA含量的影响。在采集咖啡样本时采取了预防措施，以应对OTA的不均匀性。烘焙条件保持在商业实践范围内。烘焙时间从2.5分钟到10分钟不等，烘焙颜色从轻中烘焙到深烘焙。不同烘焙时间和颜色水平之间OTA减少量的差异未达到统计学显著性。然而，对于所有烘焙条件，减少量都非常显著，综合结果减少了69%。目前共有九项不同作者关于咖啡烘焙过程中OTA减少的研究。这九项研究中有七项报告称，OTA减少的相关范围在69%至96%之间。在这七项研究中，有四项研究报告使用了天然受污染的咖啡豆、适应霉菌毒素不均匀性的采样程序以及实际操作范围内的烘焙条件。对于这种减少有三种不同的解释：OTA随谷壳物理去除、在C-3位置异构化为另一种非对映异构体以及可能涉及水分的热降解。这三种解释可能在咖啡烘焙过程中OTA减少中都起到了部分作用。
