In addition, Martine Nouet looks at new ways of approaching the flavour of food, by colour and science, while she and I debate what lies behind the technique of tasting. Like Neil Ridley's feature this dwells on how important our sense of smell is, and yet we continue to live in a world in which it is our least appreciated sense and one which has often been denigrated.
In 1798, Immanuel Kant in his Critique of Judgement described smell as being the sense "[to which] we owe the least and which seems to be the most dispensable..." His belief - still, vestigially, accepted today - saw smell as a base sense which compromised man's desire and appreciation of beauty, not to mention "good taste".
It took Rousseau for whom "smell was the sense of the imagination" (from Emile) and Nietzsche to defend smell. For the latter, it was the animalistic quality to which Kant had such a philosophical aversion, which made smell so vivid and exciting. For Nietzsche, smell was instinctual rather than intellectual, it was the sense aligned with truth, rather than logic, its "animal" qualities revealed our humanity. "All my genius," he writes in Ecce Homo, "Is in my nostrils."
You'd think that Nietzsche would appreciate that, despite years of scientific research into olfaction, we still don't know exactly how our sense of smell works. The essayist Lewis Thomas wrote: "The act of smelling something, anything, is remarkably like the act of thinking... immediately... you can feel the mind going to work, sending the odour around from place to place, setting off complex repertoires in the brain, polling one centre after another for signs of recognition, old memories, connections." On Smell (from Late Night Thoughts on Listening to Mahler's Ninth Symphony).
He's right. But what actually happens? We know that we can all detect the differences between individual scent molecules, but how we do it is a mystery. They rise up the nose - or retro-nasally (via the back of the mouth) - into our olfactory system. There, the molecules are dissolved in mucus and analysed by our olfactory receptors, and here's the problem. We don't quite know how these receptors identify individual molecules. It's either shape, where each molecule fits neatly into specific receptors; or that the receptors recognise the different vibrations of each scent molecule, a theory first posited by Luca Turin and recently gaining greater credibility.
The information is passed to the olfactory bulb which then speeds it across the brain where it is interpreted, particularly in the areas of the brain which deal with memory or emotion. We never forget an aroma, everything we have ever smelled is locked in our minds. Our brain takes the information and reassembles it into a picture. We 'see' the apple, the beach, the smouldering peat fire.
Our sense of smell jumps between the boundaries of intuition and science, the emotional and the analytical. In this issue, Martine Nouet, a firm believer in intuition, has an encounter with Bernard Lahousse, food scientist and the man behind www.foodpairing.be, a website where the aromatic web of shared aromas in foods and drink are revealed.
By sticking our noses in the glass and inhaling we slip into a recognisable, personal world, but also a new one. Aromas known to us appear but in new and different relationships. We work like art critics reading the images in our minds, discovering what tells about wood, distillation and ourselves.
We need to taste as well. Flavour is the linking of aroma and the stimulation of the taste receptors on the tongue which pick up sweet, sour, bitter, salty and umami and texture. If you examine fMRI and PET scans of the brain during inhaling and then tasting you can see how the brain reacts when we taste, it explodes into life when the liquid (for example) hits the tongue. We have to drink!
Rather than being a maligned sense, our senses of smell and taste allow us to appreciate the world. It is strange therefore that while we are still taught to look to see, say in appreciating art, but we are not (in the UK at least) taught how to smell. There's no such course as "smell appreciation", yet it gives us clues to our environment, to danger, to sexual attraction, to illness.
This is exacerbated as we get older and the habit of consciously smelling things wanes. We're happy with "fruity" rather than thinking of what fruit, we say "floral" without concerning ourselves over which flowers, and yet, the information is there in our minds. By consciously smelling and tasting we start to engage with the world.
I was discussing this with Harold McGee, the godfather of the science-based approach to cooking which has revolutionised gastronomy. "There's a growing literature in neuroscience, sensory psychology, and philosophy on the relationships among sensations via our various receptors, perception of those sensations, and various other neurological inputs, both sensory and not," he said, "but the bottom line seems to be that our experience of the physical world is highly mediated, we can compensate for this to some extent by becoming aware of and attending to our perceptions."
In other words: be aware, start smelling, tasting and trusting the pictures in your brain. We have to look deeper and revel in the miraculous array of flavours created when we manipulate a grain of cereal.
Info
Further Reading
The Secret of Scent
Luca Turin, Faber & Faber
Olfaction, Taste & Cognition
ed Ruby, Schaal, Dubois, Gervais, Holley, Cambridge
Meaningful Scents Around the World
Roman Kaiser, Wiley