Page 16 - EUREKA Winter 2017

Knowing what compounds are
present as coffee begins its downhill

slide could help Bridgehead manage
its inventory by selling at-risk beans

sooner, while rationing sales of beans
that are likely to last.

Barista Kyle Woods crafts the coffee at the core of this research.

same source each week.
Inside the mass spectrometer — a plain 1.5-metre-high
box that could pass for a photocopier — a technique
called gas chromatography separates molecules pres-
ent in the aromas. Inert helium pushes gaseous aromas
extracted from vacuum-stored coffee through a hollow
fused silica coil. Inside that slender coil — 30 metres
long but just a quarter of a micron wide on the inside — tain molecules that, on their own, would probably taste
molecules are separated based on their mass and ability terrible. Or you look at it and say, ‘Why is that in coffee?’
to evaporate. The technique breaks down the complex It’s all part of the complexity of what coffee actually is.”
aroma of coffee into component parts, allowing the
team to identify each molecule individually.
“We have data now that show upwards of 45 to 50 The study of coffee on a molecular level is an emerging
different compounds,” Smith says, noting that about 80 field, and observed on that level, it could be obvious
percent of what we taste are molecules with the ability which molecule is making good coffee go bad. But that
to evaporate from the medium that they’re in, as coffee isn’t the likeliest outcome. Luckily, it also isn’t necessary.
aromas do. “Those compounds combined together are “Even if we can’t find the root cause of the problems,
responsible for what makes coffee taste the way it does. we’ll still be able to see a problem coming before the
You can separate each one out, and the chemistry of taste gets there,” Smith says. “The reality is that we may
what’s actually in there is fascinating. You see these cer- not figure out what’s really causing it, but we can still

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