Do you like to have your nose in a book? No, we’re not talking figuratively. Something about the scent of old books can perk up any bookworm. And turns out, there’s a legitimate reason that dusty old pages actually smell good.
Most of what we smell comes from volatiles organic compounds (VOCs), which books give off as they decompose over time. University College London researchers extracted its VOCs from a 1928 French novel they found at a used bookstore. (Find out where to donate your own old books.) Volunteers blindly sniffed extracts from the book, plus seven other unlabeled scents ranging from chocolate and coffee to fish market and dirty linen. Afterward, participants filled out a survey with a question asking them to describe the smell of the historic book.
Without knowing what they were smelling, more than a third of the 79 participants said the old book extract reminded them of chocolate. Coffee was the second most reported scent, according to the study in the journal Heritage Science. Yum!
“You tend to use familiar associations to describe smells when they are unlabeled,” study author Cecilia Bembibre tells Popular Science. “And also, the VOCs of chocolate and coffee seem to be very similar to that of books.” Sounds funny, but chocolate and coffee contain fermented or roasted chemical compounds called lignin and cellulose, which are also in decaying paper, the authors write.
For another part of the study, volunteers described the smell of the library at St. Paul’s Cathedral in London, where tourists often comment on the scent. Participants filled out questionnaires as soon as they walked into the space, before their noses could get used to the scent. First they rated the intensity and appeal of the library, then picked out individual smells. The volunteers marked if they could sense any of the 21 smells the researchers picked out from a VOC analysis, and could fill in the blank with their own descriptions too.
The library scents were decidedly different from the book aromas. All seven of those volunteers said the library smelled woody, and most described it as smoky and earthy.
Noticing scents isn’t just a way of figuring out where you are—it’s also a way to reach long-forgotten memories. “Our sense of smell is very close to the memory center in the human brain, and therefore we very often associate memories with certain smells very powerfully and very strongly,” study author Matija Strlič tells Popular Science. “Very often smell triggers old memories that we otherwise couldn’t trigger. It is one of the reasons smell plays such an important role in how we experience heritage.”
The researchers aren’t just looking for an excuse to reminisce about trips to the library, though. By breaking down and pinpointing scents, they eventually hope to mimic those smells in a lab to recreate aromas from the past. “It’s not the whole picture, but it starts building communicable data,” Bembibre tells smithsonian.com. “This starts a conversation with philosophers, scientists, anthropologists, technologists, and the public itself about what we need to describe a smell.”
For now, we’ll just be enjoying the full sensory experience of our favorite page-turners—maybe with a piece of chocolate.