For those of you new to the topic I thought I’d write a brief blog to explain Sensory Science, where it started, and how it is used in the food industry. Let’s begin with a widely accepted definition of Sensory Science:
“A scientific discipline used to evoke, measure, analyze, and interpret reactions
to those characteristics of foods and materials as they are perceived by the
senses of sight, smell, touch, taste and hearing”
Stone, H and Sidel, J.L. (1993) Sensory Evaluation Practices 2nd Edition. San Diego, California: Elsevier Academic Press.
The above definition is fairly self explanatory. I also like to put it another way - there are no machines as sophisticated as the human brain, or that can give you their perception of a product better than a human, therefore sensory science uses humans as subjects to test new products. E(electronic)-tongues and e-noses are some of the latest developments in measuring taste and smell, however they can only focus on one sensory aspect at a time whereas the human brain processes many sensory aspects; taste, smell, texture, sound and appearance, of products all at once in order to elicit a response.
What are the principles of Sensory Science?
We are essentially using humans in place of machines to make judgements on products. With that in mind we want to ensure a certain level of accuracy from our humans and so the first thing we must do is test them and ‘calibrate’ them, like we would any machine before we use it. Testers are specially selected to be part of a Sensory Panel after having been screened for their sensory abilities of taste, smell, vision etc. Sensory Panel members are also regularly checked for their sensory ability as research has shown that our sensory abilities can change over time.
Next, we must develop a method of evoking a response from our assessors. You may think we can just give them the product to try, but the human has its quirks! There are well known phenomena in sensory science such as a tendency for people to rate the first thing they try more favourably than if they had been given that thing to try second, third and so on. These have to be accounted for in order to limit any bias in the measured responses and so careful timing and presentation of products to assessors is employed.
We also want to ensure some standardisation in the way assessors make their measurements so that we can do some analysis on it. We achieve that by developing measurement scales, and by training assessors on what those scales mean. Then, because we know that no human is perfect, we use statistical analyses to measure how strong or reliable the results we have captured are.
Finally, and importantly, sensory scientists have to interpret what all the results that have been collected mean and report them in a practical and usable way to product developers. Was the salt too high? By how much was it too high? Did one flavour enhance the perception of another?
Why does Sensory Science matter?
Let’s go back to the 1940’s and 50’s in the US. Foods were being developed scientifically to meet the nutritional needs of the US military. Many of these were not well accepted because although nutritious, they failed to taste good to the end consumer. A similar reaction was seen when the US government produced large quantities of nutritious food to help feed the hungry in the 1960’s and 70’s. The food just didn’t taste that great! This highlighted the importance of flavour and other sensory aspects such as appearance and smell, on the acceptability, preference and ultimately consumption of food and manufacturers began to take note.
As the food industry developed and processed foods became more widely sought after, more and more members of the food industry started to use sensory analysis to test the acceptability and quality of their products during the development phase in order to try to achieve success when launched. The principle of using a ‘panel’ also began to gain popularity. Many companies have experts in their field whose knowledge of their product is deep and critical, however this can also cause them to be a poor assessor of how it will be perceived by the regular consumer. These experts can know too much about the cost of raw materials, challenges to processing, difficulty sourcing ingredients, what their ‘boss’ is pressuring them to do etc. to make an unbiased judgement on their product alone.
Nowadays there are many food manufacturers all vying for sales. In order to get ahead of the competition and win sales they must constantly react to the consumers wants, needs and desires. Consumers are ever changing and demand more and more from their products every day, but by measuring consumer’s reactions to products using sensory analysis, manufacturers can produce products that are right and will succeed.