Give your Man On The Street a glass of wine and ask him how it tastes, and you could well get the response “it tastes like wine”. Nothing wrong with that – it is what might be described as a gestalt perception. Wine contains hundreds (if not thousands) of chemical compounds, many of which will individually give rise to different flavours, but overall the impression is clearly recognised as wine. In the same way, when someone is shown a chair they will immediately recognise it as a chair – they won’t say there are four near-vertical sticks of wood supporting a horizontal square board etc.
It is only people who are relatively skilled in wine appreciation that will dive into a more detailed description like “blackcurrant with a hint of coffee on the finish” – and if we are honest “it tastes like wine” is arguably more useful in many circumstances. Also note that, while we might be feeling superior for spotting the nuances in our glass, we are saying one of the flavours is coffee. We have an idea of a generic coffee flavour, in the same way as many have a generic wine flavour. But coffee is another complex drink that experts analyse and describe in terms of other flavours. Worse than that: wine is a descriptor that is sometimes used in coffee tasting notes, in the same way that coffee is used for wines. So in an extreme case we could have a wine that happens to taste like a coffee that tastes of wine!
Joking apart, the idea that the human perceptual system can sometimes regard aromas that are chemically complex as a single entity, and sometimes analyse them into component parts, is an interesting one. I mentioned in an earlier post that, when considering the number of identifiable aromas in a wine, a chemically complex recognisable aroma behaves like an aroma that is due to a single chemical compound. In fact, the researchers reference other work showing that the two aroma types seem to act in very similar way even at a level as low as the olfactory bulb. But surely that cannot tell the full story. It is undeniable that, for some at least, wine does not merely taste of wine. Neither does coffee merely taste of coffee.