'Warm' scents such as cinnamon encourage shoppers to spend more, new research has shown.
A team from the City University of New York, the Stevens Institute of Technology, New Jersey and Temple University in Philadelphia, Pennsylvania concluded that the "temperature" of scents in a store can have a powerful effect on what and how much customers buy.
When people experience a 'warm' scent such as cinnamon, they feel that the room's more crowded than when it has a "cool" scent - even though it contains the same number of people.
"This can lead them to compensate by buying items they feel are more prestigious," say the authors.
"Retailers can easily manipulate social density perceptions with a subtle and relatively inexpensive application of ambient scenting in the store environment."
Shops have long known that the scent of a store influences what or how much we buy: it's the reason for all those spicy scents at Christmas. And the real reason most supermarkets now have in-store bakeries is that they've realised it encourages customers to spend more on food.
As for the US bakery chain Cinnabon, it already sites its ovens at the front of outlets and sites them in shopping centres and airports, where the smell is more likely to linger. Some stores even keep sheets of brown sugar and cinnamon in the ovens in between baking sessions, just to keep the scent going.
Another study, from Washington State University and Swiss researchers, has found that a simple scent such as orange makes customers spend 20% more than a complicated one - in this case orange-basil blended with green tea.
Retailers even use scents to influence our perception of how big a place is. Scientists from Canada's Concordia University say that a scent reminiscent of enclosed spaces, such as the smell of firewood, makes us feel less anxious in a large store than a scent evoking open spaces, like the seashore.
In a small space, meanwhile, we feel less anxious when we can smell the seashore.
"Ultimately, retailers who contend with small, crowded spaces, either due to limited store size or the volume of merchandise they stock, can prevent feelings of claustrophobia by using space-enhancing scents," say the team.
"However, those following the minimalist trend may want to consider using scents that bring a sense of cosiness to the environment."
Meanwhile, another new study has shown that colourful ads are most likely to get people to spend more. According to the Ohio State University team, black-and-white ads make us focus more on basic product features, while colour encourages us to buy unnecessary extras.
"Consumers should be aware that colourful, flashy advertising can distract us from thinking about basic product features (a car with high fuel efficiency) and lead us to pay more for products with frivolous or unnecessary features (a car with nice cup holders)," they say.
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