Sensory Aspects of Off-Flavor Testing

Kilcast [5] has provided an excellent discussion on this topic and will serve as the primary reference for this chapter. The reader is most strongly advised to read his work for the detail he provides. 

Some of the more frustrating aspects of the task of dealing with off-flavors are the difficulties one may have to determine if the food truly has an off-note, how to describe it, and determine the importance to a company. The event is usually initiated by a consumer complaint (but may also originate within the company, e.g., in the quality assurance laboratory). Consumers are notoriously poor at describing an off-note 

Unfortunately, there often is very poor consensus even among trained individuals. While the consensus improves as individuals become more familiar with an off-note, there still can be very poor agreement in descriptors nsed, or estimate of intensity of an off-note. This difference can come from experience of the panelists, innate abihty to verbalize a sensory stimulus, and/or sensitivity to the stimnlus. 

Despite the problem in getting good sensory characterization of an off-note, this characterization is very important in determining the source of the problem and its 

FIGURE 7.1 A typical relationship between concentration of an odorant and percentage of the population that can perceive it. (From Kilcast, D., Food Taints and Off-Flavours, M.J. Saxby, Ed., Blackie Acad. Prof., London, 1996, p. 1. With permission.) 

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