How can flavours trick our brains into eating more or less sweet or salty foods?
To reduce the sugar and salt in our dishes without affecting the flavours in the mouth, our nose has a vital role to play.
A drop of liquid vanilla, and that's it? In her laboratory at Inrae, neuroscience researcher Charlotte Sinding is interested in olfactory and taste perception, working in particular on the cerebral mechanisms responsible for taste and odor perception, which provide a mental representation of the food we eat.canisms responsible for the perception of taste and smell, which provide a mental representation of the food we eat.
The nose more important than the mouth
The researcher has identified a link between food odors and the fundamental tastes: salty, sweet, bitter, acidic. " 80% of taste is perceived by the nose (olfactory) and 20% by the mouth (gustatory )," she explains. "On the other hand, all aromas are perceived through our nose, and only our nose. Odor compounds travel up the retronasal passage at the back of the throat to the nasal cavity. The smells of roast chicken or vanilla yoghurt are detected by the nose, not the mouth. "So, when we don't perceive taste, the problem lies with the olfactory receptor.
From vanilla to sweetness
If aroma is perceived by the nose, flavor is detected by the taste buds on the tongue, sometimes with a deceptive effect. So, when we taste vanilla, our brain associates it with sweetness. " There ' s an integrative process that takes place: we register in our memory that when we smell vanilla, the sweet zone is activated ", explains the scientist. A vanilla stick does not contain a sugar molecule. However, in the past, when the beans were presented to the King's court in Louis XIV, his cooks used them, adding sugar to cover the bitterness. " This association is cultural. "
Thus, the addition of vanilla to recipes will be perceived as a sugar supplement for the Western palate. This observation was all the more glaring in participants suffering from obesity, and these findings could make it possible to modulate the amounts of sugar in certain recipes. In Asia, the same effect is seen with lemon.
Spices to boost saltiness
For the salty side, the association is with broth, smoked garlic, bacon and, potentially, spices. To arrive at these conclusions, " the guinea pigs were asked to rank drinks from most to least salty. The results showed that with smoked garlic or bacon flavoring, participants perceived the drinks as saltier than they were. "
It's possible, then, that our brains play the role of an illusionist, naturally using food aromas to make us experience tastes. But that's not all: the tasting context also plays a key role: " If a plate is beautiful and tasted in a gourmet restaurant, we're likely to get a higher appreciation score. Brain processing is important, shaping our perception according to our individual experience and context. "concludes Charlotte Sinding. Now the researcher is trying to understand which areas of the brain are activated when this mechanism takes place.
