blogis librorum. A blog about books. Rare books.

We all know that aroma. Perhaps it evokes trips to the library as a child, or the cozy ambience of a grandfather’s study. It’s the distinctive scent of old or used books.

The Science behind the Scent

Scientists say that “old book smell” is more than just mustiness; it contains hints of grass and vanilla.  That’s because all the compounds used to make the book release distinctive odors as they break down. For example, lignin, which is present in all wood-based paper, is closely related to vanillin. As it breaks down, the lignin grants old books that faint vanilla scent. It’s even possible to approximate the age of a book based on its smell. Chemists have identified 15 substances often present in books (known as VOC’s) that degrade (and therefore emit a gas) at a predictable rate. The researcher behind the project, Matija Strlic of University College London's Centre for Sustainable Heritage, was inspired to investigate when he saw a conservator sniffing paper to assess its quality. Chemist Lorraine Gibson has taken Strlic's research further, and is working on a test to help experts date books and other paper materials based on the VOC breakdown.

Banishing Other Odors from the Library

But what if a book has a stronger (and less pleasant) odor? Cookbooks, for instance, may smell of food if they’'ve been stored in the kitchen. Other scents that may creep into your pages include tobacco or nicotine. Poor air circulation—along with the resulting mold and mildew—are also frequent culprits of malodorous pages. While an unappealing smell doesn’t directly impact the value of a rare book, it can decrease your enjoyment of that book. If that’s the case, have hope! With these tips from the Dartmouth College Library, you can rid your volumes of unwanted odor:

• Find a container large enough to hold your book, and another larger container with a lid. A garbage can and a plastic crate work well. Just be sure that the containers have never been used for food or liquid.

• Place an odor-absorbing material (like baking soda, charcoal briquettes, or even kitty litter) in the larger container.

• Gently open your book and place it flat inside the container. If you're doing multiple books at once, you can also leave the books upright, with the pages slightly fanned out.

• Put the smaller container inside the larger one, and close the lid of the larger container.

• Check the book after several days. If the book still stinks, close it up again. If the offending smell has dissipated, put the book back in your library.