AgCast: Sensory Lab

You know the holidays are here when coffee shops and stores bring out the holiday flavors. The ubiquitous scents and tastes of December and holiday cheer. It brings back memories of Christmas morning, meals with family, and all around merriment. But how do food companies choose new flavors to create those unique tastes we love so much?

Well, let's find out! You're listening to the Tea and Magic Moments Podcast where we highlight agriculture's influence in everyday moments. I'm Lauren Bath with the UT Institute of Agriculture, and today we are talking flavor. Flavor is tied to so many of the senses and impacts how we experience food, and thus agriculture.

To understand the science behind flavor, I headed to UT Center for Sensory Science, where Curtis Luckett showed me how we study flavor and some of the work they're doing to impact today's tastes. But first, I wanted to know how people experience the holidays through flavor. Thank you. So we're nearing Christmas, and when you think about Christmas, or you thought about Thanksgiving, what is that flavor that you just need to get into the holiday spirit?

Probably peppermint mocha. Peppermint, pumpkin spice, cranberry, that sort of stuff. Like I think apple pies, I don't know why, but that's kind of the first thing that comes to my mind. Cinnamon, gingerbread, and eggnog.

So what happens when you smell peppermint? What is the first thing you think of? I have this Scratch and Sniff Christmas book, and my parents said that I would scratch it and sniff it and said I would smell it, even though it was completely gone. Yeah, I was a lot of Missouri in my mind.

Grandma would have cinnamon, baking, and walking, and it's also like smell holiday-ish. I think of Christmas trees, I think of pies, I think of Christmas cookies and family. You just heard from UT students, Anna, Alina, Devon, and Connor. And I have to give a quick shout out to Abby Gas, who helped me pull UT students holiday flavors.

Now we know about the taste of the season. Let's dig into the science. I'm cursed. Look at them as a professor in food science, and I'm also the director of the Center for Sensory Science within the food science department.

So yeah, what is that? What is the food sensory lab? So our lab, our sensory service center, or the center for sensory science is just basically the lab designed to collect information about how humans interact with food. Usually it's through asking them questions.

So we have booths that are set up where you would get a blinded sample and then you would answer some questions about that food sample or that beverage. We also have things like a focus group room and then we have certain different types of instruments such as smell threshold kits, taste threshold kits, things like that, where we can get to the bottom of how good of a smeller you are or if you have any smell dysfunction, things like that. So with a variety test, you walk into a grocery store and typically you see romett tomatoes or you see gala apples and there's very particular varieties that are in just about every single grocery store across the country. Do sensory tests like this indicate kind of what varieties end up in grocery stores?

It can. It can a lot of times it's working more with a prepared food. So a company will have three or four different prototypes of a new flavor they want to launch and they want to know which one is going to be the most well-light. Sometimes they do different regions of the country with different demographics, things like that.

They also want to know sometimes about willingness to purchase. So maybe you want to buy that product after eating it. And the information can be used for a lot of different, you know, a lot of avenues. So you can, among like fruit and vegetable breeding, kind of develop more light apples, more light blackberries or something to work with where you can start to kind of understand what part of the consumer need is not being met.

So if you give somebody enough different types of apples, you understand that there's a certain group of people that have the type of apple that's not on the market right now. And with some kind of high level statistics, you can kind of understand what the apple would be like, almost like a deal apple for that group of people. And you can start to design that through conventional ways or otherwise. So what are some of the, I guess, the things that you test for flavor profiles feel mouth feel?

A lot of just the basic things you talk about with a friend after you eat a meal. So it can be everything from the appearance to the aroma, to the texture of the flavor, the taste, how much you liked it. Why didn't you like it? Why did you like it?

Was the sweetness level just about right? Was it too strong or too weak? And then we can also ask questions kind of afterwards, just like satisfaction or how full you feel, things like that. If that's an important part of that product.

And it's becoming more, I guess, becoming less sterile lately. So I'm relatively new to the field, but historically, since we've been all about limiting bias. So taking a product into a white booth, which is unlabeled, the wrapper has been removed, and you consume it in this very quiet, very isolated environment. And it's not a bad method.

It's some people have started to think that there's a better way to understand if a product is going to be successful or not. Because even, oh, we've noticed there's a lot of products that are very successful in the sensory lab, maybe aren't successful in the consumer marketplace. And so there's a lot of people trying to think about how the experience in general can be modified by the food, not just the food itself. So it's a great example of that's wine.

If you drink a glass of wine in a particular setting, it's going to have a different experience than if you drink it in a plastic cup in a white booth. It's all about the ambiance. Exactly. So that's kind of what is the newer trend is.

This context is what they came up to call it. Like using things like virtual reality, or even using things like a mock restaurant setting or creating background sounds, things like that. So right now you're doing the testing typically in that sterile white environment, correct? Or have you started testing with some of these other options?

So we do a couple of different things. So we do some take home testing where maybe it's like a meal kit and the participant would come to our lab, pick up the meal kit, go home, document the preparation of the meal kit using a phone app or something like that. And then answer some questions about how much they liked it, who their family ate it, who didn't, why and that type of thing. So for things that would be more of like a family style meal setting, that would be an ideal way to go.

We do a lot of focus groups too, where we use it to pull it out and just ask them straight up, what do you think of this food? And sometimes even though it's not very many people, like when we do a typical traditional sensory test, we're usually looking at like 120 people. For a focus group, we're looking at like six to ten. So it's not representative of the population as far as whether they like it or not, but often you can get a lot of good insights as far as like how you need to redevelop your prototypes or what could be some things you maybe need to address in the marketing campaign of this product.

Because a lot of times food is at least be purchased or driven by marketing. So if your marketing campaign is not in alignment with your product itself, then you could get a little bit of a disconnect and maybe not have a successful launch as you would have liked. That makes sense. So who are your testers?

Is that just people off the street? Basically, we're based here on campus at UT. So most of the people have an affiliation with the university some way. We have a lot of spouses of employees, spouses of students themselves, employees themselves all the way from deans all the way down to just somebody that's in an out temporary basis.

So it's a pretty diverse group, but the key is they're usually based in Knoxville and a lot of them do have some type of attachment to the university. But we compensate them. You're doing a simple taste test you get between like five and twenty dollars. Nice.

It's not volunteer work. It's always good. And when there's snacks involved at the end, I think it's good. Yeah, we typically get people snacks because we do have a lot of people that are on campus to have some snacks with their desk.

And it's also instant gratification because we give out gift cards. We don't have to carry large amounts of cash on hand. And so gift cards don't really have that instant gratification part. So you don't get to spend them right away.

I have to say, it is good motivation to get down there. If you know, there's like a good snack at the end. Yeah. We try to keep the snacks, we try to keep it good variety, but also we've had a lot of it it quite lately for a more healthy snack option.

Okay. Yeah. I could definitely see that. There's a lot of Oreos and chips and things.

That someone could either purchase a grocery store or someplace that would have gone through this type of testing. So kind of give it an end product. Kind of follow it through to the end. Yeah.

I mean, the work we do with clients is typically confidential. So, but in the general thing, we just got done doing quite a bit of client testing for different holiday launch products. So the idea would be like sometime in the middle of the summer, people would start to put their product profiles together for the holiday season. There's a lot of, I mean, you think of it from pumpkin spice things to cranberry flavor things.

Yeah. So it's pretty, everybody knows what the holiday flavor profiles are. But there's our products that are typically on the market year round. And people tend to try to introduce new products to suit that holiday flavor profile.

So in the middle of summer, the client would typically have, you know, a good idea of what they want to do. They might come to us maybe in June or July with maybe four or five really varied prototypes, maybe a wide variety of different flavor profiles. And we put it through sensory that would maybe take the flavor that looks most promising and then go work and make three to five varieties of that flavor. So if it was something like a pumpkin Oreo, hypothetically, like they would have maybe a couple different types of pumpkin Oreos and then the flavor profile that was seen to be the best would go on to the next level.

And then they would try to make a couple different formulations of that to try to ensure that they could find the one that had the highest liking. So sometimes they get diagnostic out of early, like that a lot of people would think that makes a verse or something. So they would use that in their further R&D. And then in the middle of the summer, late in the summer, they would probably do another sensory test, just a traditional, you know, blinded test to see which prototype was the most liked also, which one was going to be more likely to succeed in the marketplace through asking questions like willingness to purchase and that type of thing and maybe even do some focus groups understand better like what type of packaging and what type of marketing material should go along with that product.

And then start that process and by October, probably have on the market. So obviously saying that Starbucks is using the sensory lab, but if you're going to go to Starbucks and get a pumpkin spice latte, that particular flavor combination has gone through a similar process to get to there. So that's probably sick to say. Yeah, I know that they have a strong sensory program there and most food companies don't leave things up to chance anymore.

Historically, there's been a lot of the golden tongue thing where you'd have research chefs or product developers that would sit around and they would kind of try to ascertain which product was superior. However, we've kind of understood and moved on to the idea that that's probably not representative of the population. And it's also within the population, there's going to be subgroups that are going to like different types of pumpkin spice latte, for instance. So maybe Starbucks has a different pumpkin spice latte for the ever Midwest as they would for the Southwest.

Interesting. Not likely the Starbucks at the company. But a lot of times people will understand as demographic factors that are preferred. So flavor is regional?

Sometimes. I mean, depending on the flavor, there's definitely geographical differences in the preferred products. I think coffee is a good example of that. Like the coffee that is expected in the Northeast is going to be more of that donut shop style, you know, kind of common to your by donut and donut sweater profile.

While somebody from Seattle is definitely not going to gravitate towards that is what they expect out of a normal cup of coffee because of their experience with Starbucks being in town and all of that. So what are some of the things that go into the overall flavor experience of something? Because it's obviously there's a lot of different ingredients and they all come together to produce a final product. For sure.

And that's even beyond the food, you have a lot of things that come into the flavor profile. That's kind of that experience overall eating experience thing comes in. So that's actually some of the research we do in our lab is on the we call it the multi-sensory eating experience. So how sound and how vision and how it has hearing or how sound and vision can influence your smell or taste or something like that.

And flavor is unique because flavor is actually not a single sense. We have the senses that we are all familiar with like hearing, sight, we have touch, we have smell, we have taste. And flavor is actually a combination of smell, taste and a little bit of touch which is kind of the term we use in sensory is chemisthesis. So it's a touch receptors or maybe thermal receptors in your oral cavity that can respond to certain chemicals in the food.

The best example of this is like the spiciness of hot peppers. Spiciness isn't a smell. It's not a taste. It's a feeling in your mouth.

So all those three things smell, taste and chemisthesis coming together to create flavor. However, your brain processes a lot of information from other sensor modalities such as, you know, sight and sound. So we do some stuff with that in our lab just looking at how soundscapes can influence people's perception of wine aroma, for instance, or how the label of a wine can influence their wine aroma profile. So it is a very multi-dimensional concept.

So beyond just the three senses to make up basic flavor, it is kind of a complicated thing that your brain likes to sometimes play tricks on you. Yeah, I have an art in a marketing background. So I understand the concept of kind of eating through your eyes and the marketing that goes into all of that and the plank arrangement and how all that affects the experience of the food. But I had never thought of sound being an influence.

Yeah. And there's a really good group at Oxford that's doing a lot of research on a lot of the cross-modal stuff also. And they found some very interesting things such as people routinely match certain sounds to a taste. So like sweet tastes typically are matched with a high-pitched sound, things like that.

And actually the companies have even taken this kind of the next level, especially with wine. So like Charles Krug, it's a pretty famous champagne house. So they have an app where you can scan the barcode of your champagne and it will play a soundtrack that is supposed to highlight the flavor profile of that particular year in that particular region's champagne. So there's a playlist for your wine?

Yes. So it's actually a pretty quickly growing kind of area. It's probably the place where multi-sensory stuff has gone most mainstream, is with the sound and wine pairings. That's so cool.

So obviously you guys aren't really doing anything with wine and at that level. But what are some of the cutting edge cool things you're working on? And obviously we can't give specifics. I think for the most part we're really looking at ways to better understand texture.

So texture is really unique because it's dependent on how you treat the food in your mouth as well as the food's properties that it has. So like you don't chew an almond the same way you chew a starburst. And to be how you chew a food determines how you're going to perceive its texture. If you never bite into a food, you'll never know it's crisp.

And so we look into this kind of interplay between oral processing parameters such as like how fast you're chewing, how much side to side movement you have in your jaw, how much saliva you're producing, what's the composition of that saliva? Because certain components in saliva can actually start to break down the food in your mouth and kind of look and see how those types of things influence texture perception. And that can be, we have a wide variety of things we're looking at there. A lot of them are physiological such as your dental structure.

They're also looking at people with alopecents of smell. So there's a group at Vanderbilt who has a very good smell and taste clinic where they look at people without the sense of smell. It's so sad. It is.

It's actually more common you think about 20% of the people in the world have some type of smell dysfunction. And a lot of times it goes undiagnosed because it's people say, I don't taste good or I don't have, I don't know, you know, it's not something that comes up a lot in conversation. But the ramifications are actually kind of, you know, kind of bad, a lot of depression and a lot of lack of eating enjoyment when you don't have a sense of smell. So we are looking with Vanderbilt and a school in Germany to you, Dresden, to kind of understand how texture preferences and food preferences in general are modified when somebody loses their sense of smell because often it's not a, you know, a congenital trait.

It's more to do with an injury that happened or an infection that knocked out their sense of smell. Yeah. I remember middle school doing the Starburst test where you plug your nose and try to differentiate which type of flavor and it's impossible. Yeah.

And that's really highlights how important aroma is. And that's the color of the retro nasal route where you can actually smell stuff through your mouth. And so that's everybody's experience that if you've ever had a science infection, how do you, you know, people often say, well, I have a science infection, nothing tastes good. Or maybe you over salt your food or extra spicy food when you have, you know, a science issue.

And that's because you're basically operating without your retro nasal function. So you don't have that aroma component to flavor, which is so important. Definitely. And this is kind of a different topic than I guess what we normally cover with magic moments because we're talking about agriculture's impact in everyday lives.

But this is kind of bringing it like a step further because we're consuming agriculture and then even down to the flavor and the smell of it is impacting our mood and how we're perceiving just our enjoyment of meals and it just affects so much. Yeah, it's, you know, we are probably part of agriculture. I think that sometimes it's difficult to find common ground and alignment on the research side because we're really more looking at a lot of neuroscience or psychophysics or something. But to really enter like to support agriculture, we need to see the food product all the way through the whole system.

So all the way that, you know, that last part is kind of where we pick up, I think, and getting that product into the house, trying to maximize liking. So right now, sensory is really shifted from what it was maybe in the 70s and 80s and 90s where it was about optimizing flavor profiles to create the highest sales for this product. A lot of times, that's still the goal. But consumers have a want and a need for healthier food products.

But if those food, I mean, we've all had a health food product, it's just not up to par as far as taste and flavor goes and texture too. And so sensory now is a great way to help create a healthier food supply. Like right now in the food science department, we're working with some compounds we've isolated from mushrooms to try to reduce sodium. So these can artificially, I should say, increase your salty perception of a food and they're all natural.

They're found in white button mushrooms, but just finding them and extracting them and they can have large ramifications on the line for sodium reduction and creating a healthier, prepared food supply. Yeah. So there's this big push now to reduce sodium and reduce sugar in our processed foods. And that is directly affecting the flavors.

So yeah, what are some other ways that you're trying to bridge that gap? Well, I think one of the most famous kind of case studies on that is Campbell's soup. Just typically canned and shelf stable stuff tends to have a high amount of sodium for mostly, you know, food safety reasons, but also flavor profiles affected. They've basically learned that, you know, this is, I don't know if this is public information, but it's definitely been talked about in the sensory field is advertising your sodium reduction is a good way to make people not like the new product.

So I think- So perception of less salt? Yeah, just that big label saying like we do sodium often makes people just kind of, you know, come into a certain expectation or whatnot. So I think gradually reducing the sodium content of each individual product and maybe not making it as a, not using it to sell more of it, just doing it to make the world better place is kind of the way to go. So I think that's one really important part is that people do kind of create expectations based on packaging or based on label claims.

So those can be good. Sometimes, you know, if you're getting something very healthy, you may have to have an expectation it's more manageable. But on the other term, on the other side of things, I guess if you have a product that you know was re-engineered to be healthier, you might not like it as much as the original product. So I'm the consumer that looks for the no salt added or to do sodium in my canned beans, soups and everything else like that.

And I'm okay with that because I kind of grew up with lesser salt intake, healthy mom and all of that. So I'm not your typical consumer you're saying and you're trying to move the entire product to a lower sodium gradually or is that kind of thing? I think certain products, yeah. But there's also the typical food consumer isn't so typical anymore.

It's a really large market. I mean, a lot of people buy cars but everybody buys food. And so these small niches are huge in the food industry. So you can see how companies even like Whole Foods, Whole Foods is a very big company but it's still kind of niche.

And as I think that often if you're into food and you're close to the food industry, you sometimes forget how large the silent majority is of food consumers. Where there's a lot of people who are looking for convenience and flavor and they don't have a strong preference on the GMO issue or organic or things like that. These are the fun things to talk about. But I think if you wanted to look at like this largest chunk of the general food consumer profile, it's going to be people that are not really interested in any of that or maybe they are but it's not what's driving their decisions.

Yeah. So what prompted you to go into this field of work? Yeah, I don't really have a great like, I know, Eureka moment but I actually started out as a nutritionist and somehow ended up at a high fructose corn syrup company, which is not where most of the nutritionist find themselves. And then I kind of discovered food science through that job experience.

So I didn't really know about food science in undergrad where I went, they had a food science degree but I thought nutrition is what you did if you liked food. So anyway, it's kind of learned about food science and I was working with sweeteners and different things of that nature at this job and went to get my master's degree and I kind of actually was looking into carbohydrate chemistry. So really looking at more house starches do things, I don't remember actually like chemistry things on starches. And then I started to kind of look at the texture perception because starches often used baking and we did some serial coding things during my master's degree and it just textured like fascinated me and so I started looking into this and I realized that very few people were researching this and looking at physiological parameters and things like that.

And so I started working on my PhD looking at texture, chewing, that type of stuff and I guess they just rolled into here. That's cool. So is it kind of a growing field? Is it something that people aren't as aware of?

I think food science is definitely growing. The demand for food science is huge and within food science there's different, you know, sub fields of food science. Obviously we have people who do like food safety and food microbiology and we have people like myself who are measuring people's chewing patterns. So in general food science is a really sought after degree to have for a lot of different food companies.

Sensory is growing. I think sensory is growing quickly. I think how the training for sensory scientists, I should say, the training for sensory scientists is kind of morphing. I think people in my field come from different backgrounds.

We have people who have degrees in experimental psychology, who have degrees in statistics, who have medical degrees. And we also have people with PhDs in food science and master's degrees in food science with the specialization in sensory. So sensory is becoming, I say, more of a non-food thing. So people are optimizing the look and feel of a car's interior through sensory principles, using sensory principles to design new sneakers, things like that.

So I think that sensory is growing, but maybe not so much in the food industry as it is growing outside the food industry. So some of the varying sciences and you can apply that to food science. So what we do is very multi-faceted. So we do a lot of experimental design.

We do a lot of physiology, understanding how people actually smell or taste or whatnot. We use a lot of sometimes neuroscience or psychological techniques. And we also have a lot of statistics on the back end. So people can kind of be good any or all of those different things through a different background.

You have me until statistics. Well, that's actually probably my favorite part. I hated it when I first started, but I think it's one of those things. Yeah, that was my weakest point in my MBA, but that's all right.

Yeah, it's trying to think about analogy for statistics, but I think you can learn to love them. Yeah, well, as we're approaching the holidays, we're going to be approaching a lot of different food, a lot of different food profiles. And this is kind of an interesting look into it and in a different way to think about what you're eating, what you're drinking, and all the science behind of it. So I really appreciate you taking the time to do this.

No problem, thanks for having me. If you'd like to know more about sensory science at UT, check out ag.tenacy.edu and search for the Center for Sensory Science. For TN Magic Moments, I'm Lauren Vath. And remember, especially around the holidays, there's no magic without ag.

Thanks for listening.