科学美国人60秒 SSS 香甜可口的咖啡（在线收听）

What's the liveliest part of your kitchen, in terms of harboring bacteria? Is it the cutting board? The dish sponge? Or maybe… your coffeemaker? Because even though caffeine has antibacterial effects, it turns out espresso machines can harbor a whole menagerie of bacteria—including some pathogenic species more commonly associated with the toilet.

厨房里哪里的最容易养殖细菌?是橱柜?洗碗布?可能还是咖啡壶?虽然咖啡有抗菌效果，但结果表明咖啡机能够养殖大量的细菌——其中包括一些和厕所有关的致命细菌。

Researchers sampled ten Nespresso brand espresso machines, zeroing in on the drip trays, which catch those last drops of brown gold after a brew. They found that nine of the ten machines harbored residues rich in Enterococcus bacteria, a typical marker of human fecal contamination. And another common resident was Pseudomonas—which has both benign and pathogenic strains. Pseudomonas appears to thrive in the presence of caffeine, and break it down. Which suggests the bugs might be put to work decaffeinating coffee, or cleaning caffeine residues from our waterways. The findings appear in the journal Scientific Reports.

研究人员对10种品牌的雀巢咖啡机进行取样，集中研究滴灌托盘，方法是在咖啡酿造之后收集咖啡机中最后几滴咖啡液体。研究人员发现，十台咖啡机中有九台残留了大量的肠球菌细菌，肠球菌细菌一般存在于人类的排泄物中。而另一种常见的细菌是假单胞菌——其中包含良性和致命菌种。假单胞菌在咖啡机中大量存在，并可以自身繁殖。这表明细菌可以去除咖啡中的咖啡因，或者清理我们水道中的咖啡残留物。该研究结果发表在《科学报告》杂志上。

As for your next espresso shot? Don't worry too much. The researchers did not find any bacteria in the coffee pods themselves—so they say our fingertips might be to blame for spreading the single-celled invaders. And they write that it's "absolutely not the case" that Nespresso machines are dangerous for human health. Just wash the drip tray regularly with soap and water, as you would any other food-contaminated surface. So that the only thing brewing in your espresso machine… is your coffee.

至于是否要再喝浓咖啡?不要想太多。研究人员并没有在咖啡豆上发现任何的细菌——所以研究人员称指尖可能是细菌入侵的罪魁祸首。并且他们写道：“雀巢咖啡机对人类健康有危险——情况绝对不是这样的。只需要经常用肥皂和清水清洗滴灌托盘，并且不要用任何其他东西污染托盘表面。所以，这样的话，在咖啡机酿的唯一的香甜可口的咖啡。