See why no one can eat just one

We treat the words “taste” and “flavour” as interchangeable. But taste is unidimensional, referring only to the feedback we get from tastebuds (classified as sweet, sour, salty, bitter or umami). Flavour – our impression of a food or drink – depends on a lot else; on all five senses, in fact.

The more the senses are engaged, the more enticing a food becomes. Food scientists and experienced cooks know this and use it to their advantage. It’s why so much time, effort, money and material are spent on ensuring the right mouthfeel for packaged foods ranging from chips to instant noodles, through their extended shelf lives.

Now, two senses override the others when it comes to our experience of food: smell and sound. Sound is the less-acknowledged one, but it’s part of the reason that foods such as chips and chivda feel so satisfying.

Our love of crunchy foods can be traced back to prehistoric times. Studies suggest that, over a million years ago, homo sapiens searching for nutrition realised that crunchy foods such as insects kept them strong and healthy (insects, to early humans, would have been a vital source of protein and of minerals such as calcium and magnesium).

Crunchy plants were also an indication that a fruit or vegetable was at peak ripeness, full of water and turgor.

Crunch became desirable, a sign of a good meal. It’s why, to this day, a soggy apple or cucumber feels unpalatable. It’s also at least part of the reason it’s so hard to stop eating snacks that are crunchy; they resonate in the mind as a precious treat. (“The more the better,” the mind responds.

“Eat till it’s all gone.”)

As the human sense of flavour evolved, in those times of scarcity, the different senses evolved to play a larger role. Crunchy foods, for instance, activate proprioceptors in the human jaw. These sensors send the brain intense, granular information about foods as we eat them. Information such as the force applied to the food when chewing, the sound of the crunch, and skull vibrations all add up to create a rich, multi-sensory experience that adds to the pleasure derived from taste.

Sound has become so pivotal that a food or drink with less of an audio kick may be perceived differently by the tastebuds. Experimental psychologist Charles Spence of Oxford University conducted what he called a “sonic chip experiment” in 2014. Test subjects wore headphones while eating Pringles and listened to pre-recorded crunch sounds. When the sounds were louder, the chips were perceived to be 15% crunchier. Subjects also gave soft drinks better scores on flavour when they were fed sounds of louder-than-usual fizzing.

Aromas, of course, remain the most dominant dictator of flavour. Fragrances make their way to the brain through the orthonasal route and the nasopharynx at the back of mouth. The human nose is capable of distinguishing between a trillion different smells, with aroma also acting as a powerful trigger of memory. Those memories play a big part in what becomes a favourite food, a preferred sick food, an item we may love or abhor.

So there you have it. Your list of favourite snacks isn’t just a matter of combining salt, fat, acid and heat. It’s a dance of multiple senses, going back to precious early memories, and even further back, to the evolving survival tactics of early humans.