Influence of obesity on saltiness and sweetness intensity enhancement by odors

Abstract

Some odors have a taste dimension likely due to repeated experiences in food with tastes. These odors can significantly enhance the related taste perception; this phenomenon is called Odor-Induced Taste Enhancement (OITE). The study aimed to determine odor-induced taste enhancement (OITE) differences between obese (OB) and normal-weight (NW) people. We hypothesized that OB would perceive a higher sweet taste enhancement than NW. We also tested salty taste enhancement without an oriented hypothesis. 43 NW and 38 OB took part in ranking tasks and evaluated OITE in 13 sweet and 4 salty solutions. The sweet base solutions were apple juice (Aj), cocoa (Coc) and water. The odorants were vanillin, ethyl-vanillin, french vanilla, two lychee odorants, and furaneol. The salty base solutions were a green-pea soup and water, and the odorants were smoky bacon smoked garlic odorants. Each ranking was performed with 4 solutions, 3 with an increasing concentration of salt/sugar, and the fourth contained the lower sugar/salt concentration and one odorant. Participants ranked the four solutions from lowest to highest sweetness/saltiness intensity. As a main result, the OB group perceived OITE more often than NW. The maximum sweetness and saltiness enhancements were observed in OB with vanillin in apple juice and bacon in salty water. Our results also demonstrated that the ranking task efficiently assesses OITE and highlights subtle differences between groups and solutions.