为何要将咖啡豆保存在冰箱中

Many of us keep our coffee beans in the fridge or freezer to keep them fresh, but a new study suggests there’s added benefit to this practice: more flavorful coffee.

我们许多人都喜欢将咖啡豆放在冰箱或者冰柜中保持新鲜，但是一项新的研究表明这一做法还有其他好处：咖啡味道会更浓。

Scientists from the University of Bath, in collaboration with a local cafe, studied the effects of grinding beans at different temperatures—from room temperature all the way down to a chilly -196°C. (I guess they figured some people like to store their coffee beans in vats of liquid nitrogen.) As the researchers point out in their ensuing study, now published in Scientific Reports, we get more bang for the buck when we grind cold coffee beans. That’s because the particles within coffee beans get tighter as the temperature gets lower. So during the brewing process, we get more flavor from the same amount of coffee.

巴斯大学的科学家与当地的咖啡厅合作，研究了不同温度之下的现磨咖啡的口感——从室温一直降低到冰冷的零下196摄氏度。（我猜他们认为一些人喜欢把咖啡豆存储在液氮的桶中。）随后进行的研究结果现在已经刊登在科学报告中称，我们磨制冰冷的咖啡豆更加划算。这是因为当温度降低之后，咖啡豆的内部结构就会变得更紧凑。所以在冲咖啡的时候，与等量的咖啡相比，这种办法会让咖啡的味道更浓。

Like almost anything in the kitchen, brewing coffee is an act of chemistry. Ideally, we’re trying to coax as many tasty organic molecules from the roasted bean, which has been ground into tiny bits. The flavors that come of these coffee bean particulates depend on a number of factors, including water chemistry, the accessible surface area of the coffee, and as the new study shows, the temperature of the bean when it was ground. As the researchers point out, small and uniform coffee grounds allow for better extraction of the flavor compounds, which allows for more coffee per bean, and consequently more flavor.

就像厨房中的其他东西一样，冲咖啡是一种化学反应。理想状态下，我们都是慢慢调制，因为许多有机分子都来自烤制咖啡豆，而且已经磨制成了小分子。咖啡豆颗粒产生的味道取决于许多因素，包括水化学和咖啡的可接触表面，根据新研究显示的结果，还与咖啡磨制时的温度有关。正如研究人员指出的一样，小量的统一咖啡的磨制要考虑到味道成分的提取，还要考虑到平均每颗咖啡豆能够产生更浓的味道。