Recently, a group of French visitors in an English restaurant were served with what were for them foreign dishes--steak and kidney pie, fish and chips and roast beef. Before tackling their first English meal, each one of them carefully smelled the food and discussed its merits for several minutes. Indeed, this was a reasonable thing to do, since they were able to evaluate in advance the flavor quality of the food they were about to eat. A flavorist will automatically do the same thing—that is, smell the product before tasting it. The reason is, of course, that odor and flavor are two facets of the same sensation.
With this in mind, let us discuss the meaning of odor and flavor, examining in particular some of the latest knowledge in the field. The importance of smelling in the evaluation of a flavoring material will become apparent.
Physiology
It will help to define the subject if we outline the physiology of the olfactory process in simple terms. The central feature of the total sensory system is the primary olfactory area. This is in fact a highly sensitive odor detector (or cluster of detectors). Electrical impulses are transmitted to the brain which then acts as a microrecorder for the stimulus created. The data is stored or computerized with other relevant information such as origin of the odor, its name and its relation to other odors. The time taken to identify the stimulus is probably in the order of 100-200 milliseconds.