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In the mood to buy? According to a new study in the Journal of Environmental Psychology, people engage more with the merchandise and staff when a bookstore smells like chocolate.

Researchers in Belgium conducted a 10-day experiment at a general-interest chain bookstore, comparing customer behavior when the smell of chocolate was present to when it was not. Dispensers releasing a scent of chocolate were placed in two different locations. Researchers observed every fifth customer who came into the store, for a total of 201 customers. They observed “purchase-related” customer behaviors like looking at several books closely, reading the summaries of books, hanging out in the store, talking with staff and asking questions.

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Overall, the researchers found that patrons were twice as likely to look at multiple books closely and read what they were about when the scent was in the air. They were nearly three times as likely to interact with personnel and ask questions after browsing the whole store.

But the chocolate scent had to jibe with subject matter for customers to be more drawn to the books. Researchers found the chocolate smell was “congruent” with books in the food, drink and romance genres, but “incongruent” with history, mystery and crime books. During the experiment, sales increased 40 percent in those categories compared to an approximately 22 percent uptick in sales in the “incongruent” book genres. In addition, women were more likely than men to spend more time and buy books in the romance and cookbook sections.

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While the study was conducted in a bookstore, its results may be relevant to shop owners who are looking for creative ways to get customers to stick around longer – a field of research called “scent marketing“. “Retailers can make use of pleasant ambient scents to improve the store environment, leading consumers to explore the store,” the authors wrote. “For optimal results, retailers should also pay attention to whether the scent is thematically appropriate for the store’s products (e.g., sea breeze for a surfing shop).”

Similarly, a 2008 study published in the Journal of Consumer Research found that the smell of chocolate chip cookies made women more likely to make an impulsive clothing purchase than women who were not exposed to the aroma. Other research on scent marketing has found that relaxing smells like lavender may lower heart rates of shop patrons, making them more relaxed and thus more likely to buy something without thinking too hard about it. And scientists at Rutgers University and the University of Michigan have found that certain smells may even help consumers remember products better.

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