Old books carry with them a unique and often nostalgic aroma that many find irresistible. This smell, which can vary from a sweet, musky perfume to a fresh, grassy scent, is primarily the result of the gradual breakdown of chemical compounds found within the paper materials used in book production. As books age, the cellulose and lignin—key components in paper—begin to decompose. This degradation process releases various volatile organic compounds (VOCs) into the air.
Among the substances released are benzaldehyde, which produces an almond-like scent, and vanillin, which gives off the sweet, comforting smell of vanilla. Both of these compounds can contribute to the complex fragrance profile of an old book. Ethyl hexanol, which releases a slightly floral, lightly grassy aroma, can also be detected. These organic compounds evolve depending on the paper’s origin, the manufacturing processes used and the book's exposure to different environmental conditions over time.
The type of glue and ink used in bookbinding also plays a significant role in adding to the overall smell of old books. Some adhesives contain traces of animal glues or other organic substances, which further decompose and enhance the unique bouquets of libraries and used bookstores.
Interestingly, the scent of old books can offer more than just olfactory delight; it could also provide insights into the book’s condition through 'material degradomics'. Researchers in the field of conservation and library sciences analyze the VOCs emitted by books to assess their state of preservation and determine the necessary interventions to prolong their life.
Thus, the distinctive aroma of old books is not only a deeply evocative and often cherished experience but it also plays a practical role in the conservation of literary heritage. Whether one is reading at home or browsing through shelves in a library, the scent that rises from the turning pages is a small reminder of the history each book carries and the timeless journey of the written word.
