Now an eNose that can predict pleasantness of novel smells
Jerusalem: Israeli scientists have claimed
to have developed an electronic nose that could predict the
pleasantness of novel odours, just like a human nose.
The invention could provide a critical building block for
the Holy Grail of sense technology - transmitting scent
The new electronic system is different from the earlier
developed eNoses in the sense that it can classify even those
odour whose unique electrical pattern has not already been
recorded in its database, scientists at the Weizmann Institute
For the invention, a team of scientists led by Rafi
Haddad, trained the system to identify an odour as pleasant,
unpleasant or anywhere in between.
The pleasantness scale used for the purpose was prepared
after a survey of native Israelis who were asked to rate the
pleasantness of a selection of odours on a 30-point scale
ranging from `very pleasant` to `very unpleasant.
The data was used to prepare an `odour pleasantness`
algorithm, which was programmed into the new system.
The eNose was made to predict the pleasantness of a
completely new set of odours not contained in their database
against the ratings in their database.
The team found that the system was able to generalise and
rate the pleasantness of novel odours and the ratings were
about 80 per cent similar to those of naive human raters.
Moreover, if the odours were simply categorised as either
`pleasant` or `unpleasant,` as opposed to being rated on a
scale, the device achieved an accuracy of 99 per cent, said
the research published in PLoS Computational Biology.
To confirm whether the olfactory perception is
culture-specific or not, the team tested eNose`s predictions
-- that were based on the smell sense of Israelis -- with
that of a group of Ethiopians.
They found that the ratings of the eNose were as much in
conformity with the Ethipoians` as it were with the Israelis.
This suggests that even though different smells have
different meanings across various cultures, the eNose
performed equally well across these populations, indicating a
fundamental cross-cultural similarity in odour pleasantness.
In the report, the team argues that their research proves
that the perception of an odour`s pleasantness is innately
hard-wired to its molecular structure and it is only within
specific contexts that personal or cultural differences are
The findings may, in the future, allow for the digital
transmission of smell to scent-enable movies, games and music
to provide a more immersive and captivating experience. V