Cosmetic Innovation

Maria Cristina Valzachi

If you have had the experience of eating a delicious food during a severe flu ...

The effect of fragrances in the texture perception

If you have had the experience of eating a delicious food during a severe flu, you probably have noticed how the flavor of the meal is different from that felt when we are not sick. Despite the beauty of the dish, we cannot enjoy food with the same pleasure we get when we are well. In fact, there seems to be a lack of taste, isn’t it? Actually, there is an important relationship between the smell and gustatory system, and the latter is damaged when our ability to smell is decreased. The interaction between these two senses is well known and easily perceived, but could odors change other sensations, such as the perception of textures? What is the relationship between touch and smell?

To answer this question, one study has shown that smells are able to change the perception of people regarding the softness of tissue samples. During the study, volunteers were exposed to two different odors, lemon smell (classified as nice) and smell of animal (unpleasant), and then had to assess the softness of the tissue samples only through the touch of one hand. The results showed that although the textures were equal, the subjects rated the samples as softer when they were presented with the lemon odor than when presented with the odor of animal, demonstrating that the smell can modify tactile perception.

Another study sought to assess whether the use of different fragrances in a shampoo could alter the perception of the hair and product's texture (during and after washing) reported by participants. To perform the study, the researchers added various types of fragrances to the same shampoo base, so that the products differed only by the odor. The volunteers had to use each of the samples at home, at least once over the course of three days, and then answer an assessment questionnaire. The experiment showed that although the products were identical, the fact that they have different smells generated a shift in the texture perception of shampoo and hair, showing again the capacity of interaction between these senses.

In addition to demonstrating the influence of smell on touch, interesting in the above study is that although the fragrances chosen were very different in olfactory characteristics, all of them were nice and commercially used, suggesting that the changes generated by odors in evaluating a product does not derive solely from the fact that they are pleasant or unpleasant, but that there are other mechanisms involved in this effect. This is one more example that our perception is not formed by the senses in isolation, but by the interaction between them, as we saw in the post Perception: reconstructing the world.

Maria Cristina Valzachi

 

References

Churchill A, Meyners M, Griffiths L, Bailey P. The cross-modal effect of fragrance in shampoo: modifying the perceived feel of both product and hair during and after washing. Food Quality and Preference. 2009;20:320-328;

Demateè ML, Sanabria D, Sugarman R, Spence C. Cross-modal interactions between olfaction and touch. Chem Senses. 2006;31:291-300.

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