Odor and Nutrition Part 2 – Traits of Odors
- 25.01.2016
- English Articles
- Matthias Kotthoff
- Svenja Nörenberg
Peer-reviewed | Manuscript received: June 29, 2015 | Revision accepted: November 23, 2015
In the first part of the special “odor and nutrition” the anatomical and physiological basis of smell, as well as the fundamental vocabulary of aroma and olfactory receptor research have been outlined. This second part targets the question, which odorants exactly make up the characteristic smell of food.
Introduction
Foods are complex composed matrices of macronutrients, versatile micronutrients such as vitamins or antiox- idants, and moreover contain water, many minerals, and/or gases. All these molecules can either be odorants themselves or can be transformed into odorants in direct or indirect ways. Many interactions between food components, e.g. catalysis by metal ions or on surfaces, radical and redox reactions may influence the release, formation and transition of odorants. Also external influences like photolysis, oxidation due to atmospheric oxygen, or condensation reactions during drying may occur. In food, as a biological system, also enzymatic reactions occur, especially after the disruption of cellular integrity by chopping, grinding or mixing.
Summary
Odorants have a major importance for the evaluation of food. Thousands of odorants occur in foodstuffs, but only a small minority of them plays a role for the conscious perception of food aromas. Some odorants can be quite similar on the basis of their chemical properties but strikingly different in their sensory properties, yet others surprise with sensory similarity despite fundamental structural differences. Food aromas are inimitably composed of three up to 40 individual odorants, so that the composition of the final odors is subject to a complex combinatorial code. This makes it challenging to copy food odors in easy ways. This degree of complexity is further increased by inter-individual differences in the perception, which likely also adds to the generation of individual food preferences.
Keywords: smell, odorants, odor research, odor, sensory science, pharmacology
