Making Sense of Taste
To better understand taste, try to recall your last summer barbecue. Think of the salty crunch of potato chips, the feeling of biting into a freshly grilled sausage or that tangy gulp of lemonade…
At its simplest, taste is the transmission of signals from thousands of taste buds on the tongue, throat and roof of the mouth to the brain. However, touch, sound, smell and sight are all involved.
Those chips, for example, aren’t the same without their sound. Experiments at the University of Oxford have shown that the louder a chip crunches, the more likely the eater is to perceive it as fresh. That can of beer might also have a different flavour from one person to another. Variations on the TAS2R38 gene will change the shape of your bitter taste receptors, which determine how strongly you taste foods such as broccoli or Brussels sprouts. And scientists now believe that the way you smell, dictated by gene OR62A, may be responsible for the soapy aroma and taste some detect in that polarising herb coriander.
As recollections of summer barbecues attest, emotion and memory also significantly influence the way we eat. In the classic In Search of Lost Time, Marcel Proust stops short after tasting a tea-soaked madeleine cake. He realises the rush of feelings that the treat aroused remind him of Sunday mornings he used to spend with his aunt Leonie. What Proust understood more than 100 years ago about the happy effects of taste, neuroscientists now believe can work both ways. Warm associations with the smell and taste of Grandma’s strawberry shortcake can leave you with a penchant for strawberries and baked sweets. But beware: a foul food memory, of even one spoiled egg salad, for example, can turn
you off a dish for life.