Our own scent truth

I’ve found it very interesting to see the variation in how people perceive a scent, and part of the reason for the variation seems to be that for any given note or ingredient people have different sensitivities and tolerances to it. What is often called “skin chemistry” also plays a role, but even if you eliminate skin differences by having people smell scent strips, they will still describe a scent differently, and the differences go beyond semantics. I see a sort of a bell curve effect, where the majority of people experience the basic aspects of a scent in the same way but differ in the details, while a few people at the outside edges of the curve experience the scent completely differently, maybe because they are anosmic to some major components and/or extra sensitive to others.

For example, most people who sniff Rose Musc smell both the rose and musk components, plus labdanum and ambergris. Some smell more rose than musk and vice versa, but most people get both main components. One person wrote, however, that she gets all rose and no musk or any other basenotes at all, and another person wrote that she got all musk and zero rose. I’m guessing the people at the outer extremes like that must either be so sensitive to some ingredients they do smell in the scent that they’re not registering the others, or else they are at least partially anosmic to the ones they can’t smell.

Reviews of Andy Tauer’s new Vetiver Dance are interesting because some people say they don’t get any lily of the valley at all and others say it dominates all else on them. I’m in the middle ground because I smell a distinct and fairly strong lily of the valley note but not dominant over the rest of the scent, and I suspect most people fall into that general range. Whether people like the lily of the valley note is a different question than whether they perceive it to be there; when you read reviews of any scent, you’ll see differences both in opinion and in perception (and some, but not all, of the differences in perception will be due to the scent actually smelling a little different on different people).

One person couldn’t smell any smoke in Fireside Intense, and that is her own scent truth even though it’s surprising to others who smell lots of smoke. Perhaps she is so sensitive to something else in the blend that it wipes out her ability to smell the smoke. It’d be interesting to have her smell some of the ingredients to pinpoint what’s going on and how the scent could be altered to remove the ingredient that gets in the way for her (anosmia seems less like the culprit here because Fireside Intense has so many smoky ingredients it seems unlikely to be anosmic to all of them). I wonder if these sensitivities happen in the nose, or more likely farther up the pathway and maybe in the brain’s perception of scent? I don’t know enough about the science of smell perception to explain the differences I see, but I know they are real and sometimes large.

I have a dear friend who can detect a drop of rose or sandalwood from a mile away, lol, so she needs those notes to be very subtle or they feel overwhelming (yes, you know who you are if you’re reading!). Others can be sensitive to cedar or musk or a certain spice and it’s not that they dislike the note, but they just need it to be very subtle. I suppose you could say that’s a preference, but it’s because they are so sensitive to some notes that those notes loom over all others if they are too strong, and often what they consider too strong is a level considered yummy by many others.

When presented with an isolated aroma chemical or a perfume with a high amount of that chemical, people will have lots of common ground but major differences too. With ISO E Super, for example, some find it woodsy/cedary/ambery and very pleasant, some find it mildly unpleasant and sour, some smell vinegar or pickles, and some are anosmic to it or find it comes and goes. Another interesting example is the aroma chem methyl laitone, which is a creamy, milky, lactonic ingredient often used to soften sandalwood or white floral accords. Most people get a note of coconut from it, though not the same as coconut aldehyde. Some people are very sensitive to the coconut note and get very strong coconut even when it is used in tiny dilution in a blend, and at the other extreme some people just sense a creaminess and smell no coconut whether sniffing it in isolation or in a blend.

The upshot of all this for me is to be aware of and tolerant of our differences. Remember when you sniff or review something that your experience is just as valid as anyone else’s, but that other people may differ greatly in how they experience the same scent and their scent truth is just as real to them as yours is to you. Sometimes our tastes change with time and we come to appreciate things we didn’t like before, but some of our basic sensitivities, anosmias, and preferences will probably remain fairly steady over time.

This post isn’t meant to be very scientific, but meant just to state some observations I’ve made while working on scents. Dr. Luca Turin may have explanations for the differences we experience in perception of scents, though he may have focused more on the similarities in how we smell scents because that’s more relevant to the basic mechanics of scent perception that operate in us all, and because it is probably more important overall than our quirky differences.

There must be a fair amount of agreement in what we smell in order for perfumes to seem pretty much the same to many of us; for example, most of us perceive something like Coco as rich, warm, and spicy. But when you get into the deeper details people start to differ not just in preference but in perception too, and at least some of this individual variation seems to come from people’s different sensitivities to various ingredients, making some notes stand out to them more than others and sometimes even totally masking lighter notes.

Maybe I’ll come to understand all this better as I keep working and learning, but the topic is fascinating to me. Keeping ingredient sensitivities in mind helps me understand the variety of reactions I get from scent testers and helps me customize perfumes for people (I’ve not had time to do custom blends this year but really want to get back to it eventually).