by Lori Way, MS, RD
Can anything be more disappointing than not being able to enjoy your favorite food when you’re clogged up with a cold? In this second part of my series about taste, I’d like to talk about the importance of our sense of smell as it relates to perceiving taste. (Here is part one, if you missed it.) When you stop and experiment a bit with tasting and smelling, it really is amazing how crucial aroma is. Not only does it greatly enhance our ability to taste, but it is also linked with memory and emotion such that it can create a truly unique experience for each person.
Here are some interesting facts about smell:
- Humans can distinguish among at least 1,000 different odorants.
- Highly trained people, such as perfumers, can distinguish up to 10,000!
- There are two kinds of smelling: orthonasal (sniffing) and retronasal (via the back of the throat). Different parts of the brain are activated by each of these mechanisms.
- Try an experiment. Taste two red jelly beans, one cherry and one strawberry, with your nose pinched. You can tell they’re sweet, but you can’t identify the fruit flavor until you open your nose. That’s retronasal smelling.
Smell tells us three important things about what we’re eating:
- It helps us identify the substance (is it tea or coffee?).
- it triggers our memory so we know whether we’ve had it before and what that experience was like.
- and it triggers an emotional response to the food (is it disgusting?).
All of these can play into our taste preferences, even if we don’t realize it. If an odor is associated with something unpleasant, it can be very difficult to enjoy whatever foods have that aroma. If you’ve ever had food poisoning, you know that just the merest whiff of that food, or any others you ate along with it, will make you queasy. (I’ll spare you my olive story . . .) Luckily, tea is one of those foods that often has very pleasant memories associated with it. I’ve had many customers talk about memories of having tea with their grandmother when they were a child, or things of that nature, such that tea really gives them a “warm and fuzzy” feeling.
In our workshop on taste at The Tea Expo, we were asked to smell 14 bottled aromas (very concentrated) and identify them from a list of possibilities. All 14 were aromas common to unflavored tea, such as lavender, walnut, honey, malt, etc. We were also supposed to rank how familiar the smell was, how intense it was, whether we liked it or not, and what tea it reminded us of. You could say I really stunk at this task, which surprised and disappointed me. Many people have told me what a good sense of smell I have. Nevertheless, I only got 5 of the 14 correct. (I took some solace in the fact that the gal sitting next to me only got 2 right.) I also rationalized that “seaweed” isn’t really a familiar smell to me, so naturally I got that one wrong. But I was absolutely blown away that I missed “vanilla,” which I use all the time and consider one of my favorite aromas and flavors. Once I had all the answers I smelled again the ones I had missed, and while some seemed painfully obvious once I knew what they were, some just didn’t register. At the time, all I could think was that the aromas were so very concentrated that they just didn’t seem familiar. Another possible cause is that the aromas were totally out of context (which I suppose is part of the point in testing your sense of smell). It was just a little plain bottle, rather than a piece of fruit, for example. You see a piece of fruit and you have an expectation of how it should probably smell. You approach a little bottle, and it doesn’t give you any visual cues. Research has shown that aromas seem more familiar when they are paired with an appropriate taste. For example, vanilla paired with a sweet taste is familiar, but when paired with a salty taste seems unfamiliar (reference).
While most people don’t have these purified samples sitting around to practice with, we do certainly have smells all over the place that are easy to get our noses into. Smell fruits and vegetables, the dirt, flowers and other plants, nuts, and food extracts. Then smell your tea and see if you notice anything. Smell the dry leaves, the brewed liquid, and of course, focus on the retronasal sense as you swallow. When you sip your tea, make sure it is not too hot and aerate the liquid by slurping. This will help bring the aroma molecules to the olfactory nerve endings in the roof of the nose. And pay attention to not just the taste and smell, but also to the feelings and memories that may come to you as you sip. It’s very easy to miss these if you’re doing anything else at the same time, so try to quiet your mind a bit and slow down.
Next time, we’ll discuss the trigeminal system, which is what gives us a sense of the mouth-feel of a food or beverage (think spicy hot peppers or cool mint). And by all means, feel free to comment here about your own experiences and opinions.