smell is known as 'white smell' - the aural equivalent of white noise

From blocked drains to burnt toast, there are some smells that most of us would love to block out.

Now scientists think there may be a way of stopping people smelling unpleasant aromas by creating a blend of chemical compounds that neuralise a specific pungent aroma.

They have devised a mathematical model that predicts how humans perceive certain smells and think they could be blocked by creating what they describe as 'white noise for the nose'.

Scientists think there may be a way of stopping people smelling unpleasant aromas (illustrated with a stock image) by creating a blend of 38 aromas to create 'white smell'

While visual and audio signals are easily manipulated, because waves can be described mathematically, it is harder to use equations to describe the chemistry behind smells,New Scientist reported.

But Kush Varshney of IBM’s Thomas J. Watson Research Centre in New York and Lav Varshney of the University of Illinois at Urbana-Champaign have managed to describe different smells using maths.

The brothers have come up with a mathematical model that predicts how humans perceive the smells of certain substances based on their chemistry and physical properties.

The duo did this by matching a database of chemical compounds to perceived smells, so that a compound could smell 5.8 chalky, on a scale of -5 to 10. for example.

Two brothers have devised a mathematical model that predicts how humans perceive certain smells. Their research could one day lead to the creation of a smell-cancelling device, which could be used to block out a range of nasty smells from burnt toast (illustrated left) to nasty bodily whiffs (stock image right)

CAN SMELL TRIGGER MEMORIES? A Norwegian study recently uncovered the process behind how the brain makes smells stick to distant memories and 'inner maps'. Researchers designed a maze for rats, where a rat would see a hole to poke its nose into. When poking into the hole, the rat was presented with one of two alternative smells. One smell told the rat that food is in the left food cup behind the rat. The other smell told it there was food in the right cup. After three weeks, the rats chose the hole with the food more than 85 per cent of the time. Electrode pairs were inserted in the brains of the rats throughout. After the associations between smell and place were established, the researchers could see a pattern of brain wave activity in these areas. Advertisement

They say that a smell can be cancelled out by calculating which compounds create the opposite ratings, so that a perfectly neutral score of 0 is achieved.

Noam Sobel, of the Weizmann Institute of Science in Rehovot, Israel came up with the idea of ‘white smell’ – a specific blend of 30 compounds that can be compared to white noise for the nose.

Now, the Varshney brothers have shown that a blend of 38 compounds can cancel pungent smells such as onion and tuna.

While a smell cancelling machine has not yet been created, the pair think that their mathematical model could make it possible.

They came up with the idea having been inspired by IBM’s experimental Watson computer, which is currently learning to cook by looking at which flavour compounds different foods have in common.

Dr Sobel, who is working on his own smell-cancelling device, said that white smell itself is not very palatable.