What is it about the smell of cookies and rain?

Dorothy Winters: “It’s cookies, he smells like cookies, and the smell gets stronger when he’s in heat.” (From “Michael”)

Do you remember the 1996 film Michael, starring John Travolta, in which Travolta, as the angel Michael, loves dancing, fighting bulls, romance and tourist sites? My favourite part of the film is that Michael is irresistible to women because he smells of cookies. Yes, cookies – apparently one of the most enticing and attractive scents in the world; caramelly, sugarally, spicy, festive, good enough to eat.  Lists abound, but since scents are always tied to memories of specific times and places, and particularly people, the world’s favourite smells include the signature scents of the people you love, new car interiors, fresh air, vanilla, freshly cut grass, bacon (!), babies, barbecue smoke, hot chocolate, pine needles, gum tree leaves, new books, clean and fresh laundry (especially when it has dried in the sun), and rain (especially when it has rained on dry earth during a thunder storm).  What these smells have in common is that they are non-threatening, whereas the smells of blood, decay, chemical burning or illness means danger and most people find them threatening or off-putting.

The science behind the smell of rain

What makes the smell of rain so great? There is a scientific explanation:

“ One of these odors, called “petrichor,” lingers when rain falls after a prolonged dry spell. Petrichor — the term was coined in 1964 by two Australian scientists studying the smells of wet weather — is derived from a pair of chemical reactions. Some plants secrete oils during dry periods, and when it rains, these oils are released into the air. The second reaction that creates petrichor occurs when chemicals produced by soil-dwelling bacteria known as actinomycetes are released. These aromatic compounds combine to create the pleasant petrichor scent when rain hits the ground. Another scent associated with rain is ozone. During a thunderstorm, lightning can split oxygen and nitrogen molecules in the atmosphere, and they in turn can recombine into nitric oxide. This substance interacts with other chemicals in the atmosphere to form ozone, which has a sharp smell faintly reminiscent of chlorine.” (by Elizabeth Palermo on LiveScience)

For people who live in a place with an arid climate, the smell of rain is particularly appealing and quite distinctive.

If you like it, he can bottle it

There is a school of perfume makers out there that are intent on making perfumes that are the essences of your particular favourite smells even if they do not come from flowers. If a specific odour provokes memories of good times, New York alternative perfumer (or “Olfactory Artist”) Christopher Brosius will bottle them for you. Brosius makes scents that smell of real things in his “I hate Perfume” gallery. Explains Brosius: “The French are not afraid the way people naturally smell and perfume is used to make that really sexy, erotic and attractive. I can make a scent to evoke a sexy unwashed body. Certain parts of the human body smells sweet and spicy. There are lots of foods that smell wonderful. Bacon is divine.” (From the 2011 BBC FourTV series, Perfume)