People take smaller bites of their food if it has a strong smell. This conclusion could lead to the new food items which are 'extra filling'.
During the experiment, subjects sat on a dentist's chair with a tube which piped vanilla custard into their mouths. Simultaneously, an olfactometer pumped a strong vanilla custard aroma, or an aroma ten times weaker, or no aroma at all into their nostrils. The subjects could control the size of the morsels entering their mouths by pressing a button which stopped the pump immediately. It was a small experiment involving only ten subjects.
The test persons took smaller 'bites' when they were exposed to an aroma. The impact is small, the morsels being only about five percent smaller. But the impact was significant when there was a strong aroma. Then something strange happened at the second bite after smelling the same aroma. The effect was reversed: subjects who were not given any aroma seemed to take smaller bites. 'We don't quite understand why yet,' says research leader René de Wijk of the Food and Biobased Research team.
The results in this experiment tie in with earlier research findings that food texture can influence bite size. As the experiment is a pilot study conducted on a limited scale, more experiments will have to be carried out. De Wijk: 'We want to know, for example, if this applies only to combinations of aromas and food which don't belong to each other.' Moreover, tests have to be done with more subjects, aromas and aroma intensities.
In any case, the results at this stage are of potential interest, says De Wijk. His associate at the Division of Human Nutrition, Kees de Graaf, has proven earlier that people who take smaller bites also eat less as a whole. Any change in bite size, no matter how small, would be significant when new types of food are introduced. De Wijk: 'Many weight problems can be solved by eating just five to ten percent less.'