The Smell of Books

 That wonderful rich smell of books, old or new, with that inherent variation ingrained, which lures seekers of knowledge since at least the time of Egyptian papyrii. Bibliosmia is actually a word, found in the Macmillan dictionary, although not exactly officially sanctioned, but pending its acceptance.

Recenty Powell's and Demeter tried to convey that with the word "biblichor", a play on the scientific, yet poetic, word petrichor, for the scent that erupts from the rock and the soil after the rain. The suffix ichor (borrowed directly from the Greek ιχώρ) means "the blood of the gods", and honestly I could not think of a better word to convey the magical properties that a good book can convey. 

Scent must be at the heart of the following statistic by the UK Reading Habits survey conducted in 2015, which showed that 71% of respondents didn’t use e-books at all, and 76% preferred the traditional book to its electronic equivalent. Holding a book is a multi sensorial experience, with touch being the second best aspect of it; just imagine rolling your fingers over the exceptionally smooth pages of a glossy coffee table book with big pictures, contrasting with the slightly grainy surface of an old paperback you picked up at the very last minute at an airport to pass the time during a long and boring flight... 

Like with many things, the scent is embracing death and decay, as contradicting as that sounds. Perfumephiles have long known, through exposure to their hobby, that a certain degree of death is a necessary component of any potent and poignant blend. Flowers wilting into the fat of enfleurage, a traditional method of extracting precious oils, are slowly dying in front of the perfumer's eyes; essences mimicking the genital regions' scent of animals, prized in perfumery for centuries, inadvertently recall that the animals will not be reproduced after all. 

Bibliosmia is therefore also caused by the chemical breakdown of compounds within the paper, which give a sweetish smell, both figuratively and literally, thanks to the preponderance of vanillin in the final outcome. The slow death of the book, eroding through time, sometimes a very long time, is accountable for the bettering of the smell the longer the book sits. Paper contains cellulose and lignin (a polymer of aromatic alcohols, accounting for the yellowing of the pages as well). This breaks down to vanillin and turns sweet and enticing. Older books also contain other chemicals nevertheless, including benzaldehyde (the smell of almonds), furfural (also almondy), ethyl hexanaol (faintly floral), toluene (a sweetish smell), and ethyl benzene (sweet as well). The older the book, the more lignin it contains, and the stronger the scent. 

New books on the other hand hold the aroma of adhesives, paper, and modern ink as well. The smell of the Xerox room is unmistakable, due to the odor of the inks and petrochemicals. Modern binding adhesives can be based on co-polymers, one example of which is vinyl acetate ethylene, while the treatment of the paper with chemicals, although odorless to begin with, results in various reactions within which produce varied results via the emergence of volatile organic compounds. 

Chemicals such as sodium hydroxide, commonly known as ‘caustic soda’, can be added to increase the pH of the paper pulp and cause fibers to swell. These are then bleached with hydrogen peroxide, among other solubles, and mixed with large amounts of water. This water is also full of additives which modify the properties of the paper, such as alkyl ketene dimer which aids in making the paper somewhat water resistant. Newer paper has undergone processing to remove lignin, but cellulose breaks down all the same in newer books as it does in old, so the aroma is there, if somewhat different. 

 On the whole there is a dearth of scientific research on what exactly makes "new book smell", which I hope to be amended in the following years.