The science of tasting beer

Monday, June 22, 2015
Flavour is a wonderful thing, yet an enormously complex concept to get your head around.

We all know that aroma plays a huge part in flavour, but actually it is the combination of all of our senses; sight, smell, taste, touch (mouthfeel) and even sound that make up the ‘flavour’ we perceive - try eating a crunchy tortilla chip with earplugs in and it won’t be the same experience.

Years ago we used to think that different parts of our tongue were responsible for detecting the different elements of taste – sweet at the front of the tongue, bitter at the back, sour and salt down the sides – but it has since been proven this phenomenon is more to do with how our brain processes the flood of information than it is the anatomy of the tongue.

Whilst different parts of the tongue might have tastebuds that are very slightly better at detecting sweet, salt, sour, bitter or umami, every one of them is perfectly up to the task of tasting anything, so forget that colour-coded tongue flavour map you drew in school.

But as I mentioned, flavour is about so much more than the tongue. As any lover of craft beer knows, aroma plays a huge part in our enjoyment of beer, and the aroma you detect through your nostrils (known as orthonasal olfaction) affects the way you taste the beer.

Except it’s not that simple. As well as the aroma we get through our nostrils there’s something else going on too - retronasal olfaction. This is the chemical reaction which occurs where your nose and mouth meet. Essentially this is the aroma that is created and detected inside your mouth as you drink a beer, and it plays a huge role in how you perceive flavour. In fact the combination of these two ways in which we smell contributes up to 80% of the information we perceive as flavour. Our tongue can only detect those basic five tastes, but your nose can identify thousands of different aromas.

So if our sense of smell plays such a huge role in how we perceive the flavour of a beer, what can we do to maximise the drinking experience? Well first of all, you need to use the right glass.

If the beer is the music, then the glass is the speaker – it plays a huge role in your enjoyment of the beer by changing the way in which the volatile compounds (the particles our nose detects as aroma) are directed and presented.

Try it for yourself. Grab an aromatic, hoppy beer and pour it in equal measures into a straight sided tumbler and a large red wine glass. They will smell completely different, particularly as you drink, when the aroma compounds are disturbed and projected out. You’ll get a much more pronounced aroma from the wine glass than you will the straight sided tumbler, which is why certain styles of beer glass are better for different types of beer.

That doesn’t mean every beer will taste better in a balloon or tulip shaped glass though, as not all beers are at their best with the aroma turned up to eleven. Some beers, such as a well-hopped pilsner can actually taste better in a longer, thinner glass, not only because it shows off the wonderful colour of the beer, but also because it seems to slightly mute the aroma whilst accentuating the bitterness. Leading to the perception of a crisper, drier, more refreshing beer.

The way you pour a beer can affect the flavour too. Pulling a pint through a sparkler creates extra body and a larger, creamier head, pushing more of the volatile aroma compounds into the head of the beer, but it also knocks some of the condition out of the beer itself and ultimately changes the mouthfeel and flavour. Whether that’s a good thing or not depends on personal preference, but what we can all agree on is it changes the way the beer tastes.

Flavour is your brain’s attempt at decoding a flood of information from your senses into something which we can understand and react to.

So next time you try a beer and don’t like it, just remember, it’s all in your head, and you’ve only yourself to blame.

This article first appeared in Ferment Magazine