What makes a perfect cup of coffee? Algonquin students brew up an answer
Applied research could have applications for those who make beer, cheese and honey
Is a fine-brewed dark roast any different from a cup of instant? Or is coffee just coffee?
Biotechnology students at Algonquin College have been working all year to try to figure out what makes a perfect cup of joe.
"Coffee smells like coffee ... but there are subtle differences," said professor Martin Lee, who led the applied research project.
"You know what you like, so you know which of those brands are giving you those small molecules that you're after. What we're now able to do is go through and find those molecules and tell you why it is [you prefer] this brand."
Wielding the spectrometer
Lee and his students undertook the project on behalf of Sky Blue Coffee, an Ontario-based Jamaican coffee company.
The company wanted to know the properties of their beans and to compare them to beans from Starbucks and Maxwell House.
The results of the project are being presented Friday, at the college's first applied research day of the 2017-18 academic year.
The machine at the centre of the project — called a Headspace Gas Chromatograph and Mass Spectrometer, or HGCM Spectrometer — is all about smell. It heats up coffee beans until they produce vapour, which is then analyzed to determine its individual compounds.
The students used the machine to measure acidity, colour, and "total dissolve solids" — how much of the coffee grounds actually ends up in the water — as well as the chemical composition of the sample.
This allowed them to identify the flavours of each bean and make roasting recommendations tailored to the drinker's specific tastes — for instance, a predilection for full-bodied or light-bodied roasts.
Beer, honey next?
Lee told Ottawa Morning the students found relationships between a coffee's acidity — which drinkers perceive as bitterness — and the size of the grounds.
They noted that darker roasts tend to be more acidic in water and have fewer dissolved solids, implying that darker roasts create more organic acids.
We're not talking about the differences between vinegar and water here. They are small, subtle changes.- Professor Martin Lee
"The overall conclusion was that the same flavours are generally there in all of the coffees. There are subtle, subtle small differences — and that's where individual preference comes in. We're not talking about the differences between vinegar and water here. They are small, subtle changes."
Lee said the team hopes their findings will help inform clients about optimal storage temperature, proper roasting times, and the effect grinding styles have on coffee's taste, smell and appearance.
They plan on using the same technology to analyze beer, cheese and honey in the future.
Since access to a HGCM Spectrometer is normally beyond the ability of independent brewers and other food producers, Lee said there's the possibility for partnerships with Algonquin College.
"It really does enable smaller companies to approach Algonquin. We can now run quality control for them," Lee said.
"This machine, it turns out, is not the sort of thing you can buy for your household."
CBC Radio's Ottawa Morning