02 Nov 2016
Individuals are different when it comes to things like height, weight, hair colour, etc. We can easily see these variations, but what about differences between sensory abilities; such as smell, taste, etc. How much do these variations matter when recruiting panellists for an expert sensory panel?
Expert or objective sensory panels are normally used in a fashion similar to an analytical instrument. These panellists are not asked to comment on personal liking or preference, but to give objective ratings on the sensory properties of samples, and therefore, training is given to minimise variation within and between individuals. In this context, individual differences appear to be a challenge, but could they also be an opportunity?
This topic has practical implications for many food manufacturers and retailers, and was a theme of the IFST SSG (Sensory Science Group) conference held in London in June. The points discussed in this article review and expand on presentations given at the conference.
This was one of the themes of the ‘Challenges of Individual Differences’ session at the recent ‘Global Ethical and Safe – Challenges and Solutions for Modern Sensory and Consumer Science’ IFST Sensory Science Group conference.
Current research is focusing on reported perceptions and/or the ability to carry out tasks such as identify, describe, and discriminate sensory stimuli. But increasingly, there are attempts to correlate these abilities with physiological traits (such as number of taste buds) and/or genetic make-up. Newer phenotypic classifications, such as thermal taster status, may also have a role to play. Thermal taster status refers to an individual's perception of basic tastes in response to a warming or cooling stimulus applied to their tongue.
There are differences between demographic groups in some perceptual areas. For instance, we know that on average, the elderly tend to be less sensitive to taste than younger people, but may be better at detecting a mouth drying sensation. Another example is that women tend to have better odour memory than men.
As interesting as these differences may be, it is vital to remember that these trends are on average: individual variation is considerable, and individual experiences, behaviour and psychology play an important role. For example, in most cases, odour recognition and description can be greatly improved with training.
When setting up an expert sensory panel, we try to recruit and screen individuals who are best suited for the task based on the overall objective of the research or testing. This has historically meant looking for those with above average sensory abilities, particularly in taste and smell; and with motivation to participate, and good team-working skills.
In the future, the traditional approach to screening will still apply, but there may be more targeting of specific types and levels of sensory abilities. For certain panels (such as those evaluating basic tastes or odours), the use of genetic testing may help screen large numbers of individuals in the first instance, and narrow the field to those who will be asked to complete what can be expensive and time-consuming practical screening tests and personal interviews. This could ensure that enough individuals are found that are best suited for the context of testing; but would such an approach be seen as ethical? And would this type of approach reduce generalisability of findings?
Regardless of how we measure and leverage individual variation in sensory abilities, it is important to remember that a big part of sensory panel work is always going to be creative and involve teamwork, and also, that above all, sensory panellists are human(!). So we must always treat our sensory panellist colleagues with respect, and as the valued individuals they are.
For more information/background please see the 2016 IFST SSG conference presentations from Lisa Methven (Reading University), Isobel Payne (Nottingham University), and Carol Raithatha (Carol Raithatha Ltd.).