How do background music, the shape of a spoon, and your DNA affect taste? These are just a few of the questions that psychologist Charles Spence looks at in his research in the emerging field of gastrophysics. This week, Dan talks with Charles about the subtle factors that affect our perceptions of food. Then, Dan and his daughter Becky put the gastrophysicist’s theories to the test at a neighborhood ice cream stand. The results of their homespun experiment may surprise you!
Interstitial music in this episode from Black Label Music:
- "Private Detective" by Cullen Fitzpatrick
- "On The Floor" by Cullen Fitzpatrick
- "Stay For The Summer" by William Van De Crommert
- "Midnight Grind" by Cullen Fitzpatrick
- "New Old" by JT Bates
Photo by Sam Frost (courtesy of Charles Spence).
Dan Pashman: Alright, let's just do a sound check. First, can you test the microphone please?
Becky Pashman: Testing, testing, testing.
Dan Pashman: OK, can you tell me your name please?
Becky Pashman: Becky.
Dan Pashman: Becky what?
Becky Pashman: Pashman.
Dan Pashman: Hey, that's the same last name as me.
Becky Pashman: Yes.
Dan Pashman: Why do you think that is?
Becky Pashman: Cause I'm you're daughter probably?
Dan Pashman: Oh, right. I forgot. How old are you?
Becky Pashman: Six and a half.
Dan Pashman: OK.
Dan Pashman: A while back, before COVID, my daughter Becky and I set up a stand right on the main street in Greenlawn, New York, the small town outside New York City where we live. At first glance it looked a lot like a lemonade stand, except for our sign:
Becky Pashman: Free ice cream for science.
Dan Pashman: Free ice cream for science. And now what does it say underneath that?
Becky Pashman: Try two kinds of ice cream. Answer two questions about the ice cream. Enjoy.
Dan Pashman: And the way that we're gonna distinguish the two ice creams that we're serving today is that we have two different kinds of plates. Can you please describe the two different kind of plates that we have?
Becky Pashman: One plate is square shaped and is black.
Dan Pashman: Right.
Becky Pashman: And the other, circle-shaped and it's a white plate.
Dan Pashman: And we're doing a scientific experiment here. Is that right?
Becky Pashman: We are!
Dan Pashman: So what exactly were we studying? And what did we find? Later in the show, all will be revealed.
CLIP (BECKY PASHMAN): OHH. So I get it. You were tricking them.
Dan Pashman: This is The Sporkful, it’s not for foodies it’s for eaters. I’m Dan Pashman. Each week on our show we obsess about food to learn more about people. The experiment Becky and I were doing was inspired by the work of a researcher named Charles Spence. You know, we think of taste as something that happens on our tongues and in our noses, right? But Charles’ work has shown that taste is actually something that happens in our brains. I think the best way to explain is with an analogy.
Dan Pashman: So when you watch TV, you know the sounds of the actors’ voices are coming out of speakers in your TV. But your brain matches the sounds to the images, so it seems like the voices are coming out of the lips on the screen. Your brain synthesizes different inputs into one single experience. Well, the same thing happens when you eat and drink. Yeah, you get input from your tongue and nose but there’s so much more:
Charles Spence: The shape of the glass matters. The weight of the glass matters. The weight of the cutlery in your hans matters. It changes how tasty the food is. It all gets blended together in a way that’s kind of impossible for you to pull it apart.
Dan Pashman: This is Charles Spence. He’s a psychologist at Oxford University in England, and he’s a pioneer in a field called gastrophysics. His research has shown that what we think of as taste is actually influenced by a wide range of other hidden factors, way beyond the list you just heard. In a way Charles and I are kindred spirits. We’re both obsessed with the tiniest details of the eating experience. The difference is that while I have literally worn a lab coat on TV, he does real research. Today, we’re gonna dive into his work to uncover many of the factors that influence taste starting with DNA.
Dan Pashman: For instance, some people are super-tasters. They’re just born more sensitive to certain flavors. Charles uses tasting strips in his research. You put this little piece of paper on a person’s tongue, some people taste nothing, others recoil in disgust because it’s so bitter. As I told Charles, my wife Janie and I have actually taken that test. To me the strip was super bitter. To Janie – nothing.
Charles Spence: I have heard from others sources as well that when they've taken the super taster test, it has explained some of the tensions that were in the households. And for myself, it was my father as child, and we'd sit a the dinner table and it's kind of a traditional family. And my father would force us to eat all of the vegetables on the plate before we could have any desert. And we used to hate him, and my brother and I are sixty-years-old, and he still hates brussel sprouts for the bitterness. And when I finally got to give my whole family the tasting strip, I found out that my dad can taste nothing. He's a non-taster and the rest of us, my mother, my sister and my brother, my nieces and myself, we're all get a quite strong response. And it explains the decades of....I wouldn't quite call it abuse but certainly a tension at the dinner table.
Dan Pashman: So when you gave that test to your father and your family members...
Charles Spence: Mm-hmm?
Dan Pashman: How did, having that new knowledge, that your father was tasting this food in a totally different way than the rest of the family was, did that make you feel somehow compassionate towards him? Did it make you want to let him off the hook or did it make you angrier with him for having forced you all those years?
Charles Spence: No, no. It just sort of gives you an explanation for things that were kind of mystery before. You know, why would somebody make you do that, eat all those horrible tasting vegetables? Don't they realize how bad they are? I mean, what are they trying to get across by making you? And to understand that we actually live in different taste worlds. Something that maybe we never intuit if we think about it. It's sort of there in the background and can explain a lot of the differences and some of the debate, disagreements that results there. I think it was good to know in the end. A bit late for my brother. He's still, you know, he remembers fifty years ago looking at the dinner table.
Dan Pashman: So when it comes to Brussels sprouts, Charles is sensitive. But he also has his blind spots.
Charles Spence:I'm completely anosmic, that is unable to smell cork taint in a win.
Dan Pashman: Cork taint? That's like when the wine's gone bad, right?
Charles Spence: Yes. Yes. Yes.
Dan Pashman: So I could take some wine that's gone totally bad, pour it into a fancy bottle, some you know Château Lafite Rothschild, 1968, and serve it to you.
Charles Spence: Yup.
Dan Pashman: And you'd pay me a thousand bucks for it.
Charles Spence:Right, and I mean that's what my friend's do.
Dan Pashman: Do you find that your friends often want to do experiments on you?
Charles Spence: And vice versa, yes. Yes. It's what psychologists get up to when they have a good time.
Dan Pashman: Right. I mean, what's it like to go out to dinner with you?
Charles Spence: ahh....hmm. Fun, I think? I guess...
Dan Pashman: Maybe I should get your wife on the line and ask her.
Charles Spence: Going out is, on the one hand, interesting just cause always more experiments to be done. And just going out you can sort of see what sort of things people are doing, or you get ideas. Funny, sometimes you go out to a restaurant, as I did in Barcelona, and the chef there was just serving all the food from one side of the plate and the other side of the plate was black, and that got me thinking why. And we got to speak to the chef and he couldn't really say why, just had seen it somewhere else. And then we thought, let's get in to experiments there after saying, OK, I wonder what really happens because I don't think it's gonna work. I think people will not pay as much for asymmetrically plated food and that's what we later found.
Dan Pashman: These kinds of details are a big focus of Charles’ work. He hosts a monthly dinner at his home where he runs all kinds of tests on his guests. Like he’ll change the color of the lighting with each course to see how it affects the taste of the food. One time a chef came over, cooked rabbit, and covered the handles of the silverware with rabbit pelts. So as you ate, you were also feeling and smelling the pelt. Not sure that cutlery gonna be available in the PETA online store any time soon. But a lot of Charles’ experiments look at more everyday aspects of the eating experience.
Charles Spence: The weight in the hand of cutlery, but also of plateware, glassware, bowls, pots, mugs, seems to translate into a better, a more satiating experience of the contents. It's as if our brains don't do such a good job of distinguishing the food or the drink from the container or receptacle or cutlery used to get it into our mouths. This particular result came from an experiment. A series of experiments, in fact. Some that we did in lab in Oxford, but then also followed up in a large restaurant study and the main course was salmon. And half the table, the diners were about 70 people, ate that main course with light canteen knife and fork. Those sitting at the other table, the other 70 or 80 people, got to use the very heavy cutlery that the restaurant normally uses. And we asked people to rate how much they like the taste of the food, how much they'd be willing to pay for a dish like that in a restaurant, like the one they were sitting in. And they were able to show a significant increase in the willingness to pay for exactly the same dish, on exactly the same day, simply as a function of the weight people were holding in their hands.
Dan Pashman: And the feeling, you know, that sense of feel when we eat is important, you say, not only in the utensils and the plates, but also in also how the food, itself, feels in our hands. You said you have a colleague who did this really interesting experiment with soft pretzels, like fresh baked pretzels.
Charles Spence: Mm-hmm.
Dan Pashman: Tell me about that?
Charles Spence: This was a colleague, Micheal Bonarti Cohen over in Canada, who did a laboratory study gluing together half a fresh and half stale pretzel.
Dan Pashman: Gluing together?
Charles Spence: Yeah.
Dan Pashman: He, literally, cut pretzels in half...
Charles Spence: Don't ask me about the—whether with sellotape or pritt stick of who knows what.
Dan Pashman: Right.
Charles Spence: But put them together and without the subjects knowing. So they were asked to pick out the pretzel at one end, so they'd either a very fresh or a very stale one and then bite into the other end. Stale if you held fresh, fresh if you held stale. People were asked to rate the perception of the food in their mouth. What he was able to show was that the feel of the food in the hand did set expectations about what was about to go into your mouth and those expectations that we find time and time again kind of anchor the tasting experience. And very often we live in a world where what we expect it taste as much as what we actually do end up tasting.
Dan Pashman: These days Charles is working on ways to upend expectations and revolutionize one aspect of the eating experience in particular.
Charles Spence: If you look at all of the innovation and exciting things that have been going on, both with sort of modernist cuisine and kind of science in the kitchen, the way that we prepare food, the way that food is plated, and you contrast that with how little innovation and exciting stuff has gone on in the world of cutlery, that has been kind of a boring stainless steel silver. The same, pretty much in design, for the last century. If you go back a century or more and those 100 piece cutlery sets. Today, we have very little range or variety. It's really really boring. And it's kind of really bizarre that, you know, we're all willing to go to restaurants and stick in our mouths cutlery that has been in, who knows, how many other people's mouths before hand does nothing else we do that for. And you think, "Well, is that the best way to do it?" If you knew what we now know today about the way the tongue is wired up, the lips are wired up, the way that we experience taste and texture in food, why wouldn't you do something differently so that you can design cutlery, just the way that tooth brushes are designed these days to optimally fit into the mouth and to stimulate the taste buds and the lips; some of the most sensitive bits of our anatomy we've got and you can do a much better job, I think, of ornanting and enhancing the tasting experience, either by eating with your hands, because the first taste is in a way with your hands or with a kind of neuroscience inspired cutlery as more texture and interest.
Dan Pashman: And so where's the future? Where are we going with all of this, Charles?
Charles Spence: We do have a set of beautifully textured spoons from a studio, really a small commercial producer in the Cotswolds. And these kinds of spoons are elegant to look at, which is important to my wife, but also come with dimples and ripples on the spoon.
Dan Pashman: Dimples and ripples on the handles or on the spoon, itself?
Charles Spence: On the spoon, itself.
Dan Pashman: And what purpose does that serve?
Charles Spence: It's interesting. It's unusual. It's different. It's a first step and now we're just gearing up to do the gastrophysics experiments to work with the cutlery makers and with the chefs to see exactly which foods might enhanced on which kind of spoon.
Dan Pashman: Coming up, more with Charles Spence, including the revelation that Chipotle plays faster music during the lunch rush. He’ll explain why. Plus, we’ll check in on the ice cream stand, where I have a run in with a bug, and my daughter offers her services as a radio producer.
[Becky Pashman humming]
Becky Pashman: Daddy, it's gonna be important to regulate...
Dan Pashman: That's OK, I'll cut out the part where I flicked the bug away.
Becky Pashman: OK. And you'll cut out—and you'll cut out the part when you say, "I'll cut of the part when you flick the bug away.", and that part I just said?
Dan Pashman: Yes. I don't know. Now, maybe not. We'll see.
Becky Pashman: It's really not part of the radio taping.
Dan Pashman: OK.
Dan Pashman: That’s all coming up, stick around.
+++ BREAK +++
Dan Pashman: Welcome back to The Sporkful, I’m Dan Pashman. In last week’s show I talk with chef and food stylist Elle Simone Scott, who’s also a contributor to America’s Test Kitchen’s TV show. Elle tells me about the weirdest thing she’s ever done to make a food look great in a photo.
CLIP (ELLE SIMONE SCOTT): For a breakfast shoot, I literally had to scour through maybe three economy sized boxes of cornflakes for perfect cornflakes for just one bowl of cereal.
CLIP (DAN PASHMAN): You mean, like you were literally going through every single flake.
CLIP (ELLE SIMONE SCOTT): Every single flake.
CLIP (DAN PASHMAN): Every flake had to be right.
CLIP (ELLE SIMONE SCOTT): Yes. There's a certain diameter, can't be folded, like...
CLIP (DAN PASHMAN): Can't be folded, Elle?
CLIP (ELLE SIMONE SCOTT): Yeah, no.
CLIP (DAN PASHMAN): Those are some of the best cornflakes! This is very subjective.
CLIP (ELLE SIMONE SCOTT): That's why they're all in the box.
Dan Pashman: Our conversation also gets personal when Elle talks about her battle with cancer, and how it’s affected her relationship with food. That episode is up now, check it out.
Dan Pashman: Before we get back to Charles Spence, let’s check in on the ice cream stand, where remember we were serving two types of strawberry ice cream. One on round, white plates. The other on square black plates. My daughter Becky was joined by her friends Charlotte and Olivia, who tried to help wrangle us some customers.
Kids: Free ice cream for science! Free ice cream for science! Free ice cream for science
Becky Pashman: No one's coming.
Dan Pashman: But eventually, people started showing up.
Dan Pashman: So you're gonna eat two kinds of ice cream.
Dan Pashman: And you're gonna answer a couple quick questions about them.
Sean: Sure. `
Dan Pashman: All right, great. Can you tell me your name, please?
Dan Pashman: Sean, do you like ice cream?
Sean: Love it.
Dan Pashman: OK, great. Do you think you're an ice cream expert?
Sean: I don't know if I'm an expert but I'm good at it.
Dan Pashman: So Sean, what was the final verdict?
Sean: The final verdict is that the white plate is sweeter.
Dan Pashman: What's your name?
Dan Pashman: Priyanka, you just ate the two ice creams.
Dan Pashman: What was your thoughts?
Priyanka: The white plate, that one was a lot more bland than the black plate one/. I thought it was less sweet.
Dan Pashman: You thought the white one was less sweet.
Dan Pashman: Interesting, OK. All right, can you guys tell me your names please?
Alex: I'm Alex.
Colin: I'm Colin.
Dan Pashman: And you guys have just tried the two ice creams. What are your thoughts?
Alex: I thought the first one was sweeter, definitely.
Colin: Much sweeter.
Dan Pashman: Which one? That was the white plate one?
Colin: The white plate.
Amelia: Um, the white one is sweeter and I don't like the red things in it.
Dan Pashman: The white one was sweeter and you didn't like the red things in it? Can you tell me your name, please?
Dan Pashman: Amelia, how old are you?
Person: They taste real similar to me.
Dan Pashman: OK. You can give the same score to each.
Person: Yeah, I would give them the same score. I mean,
Dan Pashman: I don't wanna...see, I can't bias his judgement, otherwise this entire extremely high tech science experiment....
Dan Pashman: Like we might end up in National Geographic with this thing right here.
Person: It looks that way. I like it.
Dan Pashman: So come over here and I'll tell you the secret.
[Kids: Free ice cream for science!]
Dan Pashman: So, it actually is the same ice cream in each one, but we're testing here is how the color and shape of the plate...
Person: I like that.
Dan Pashman: Affects how your ice cream tastes.
Person: Ahh, that's some good science. All right, now do I throw this out somewhere over here?
Dan Pashman: Yeah, yeah. The garbage is right there.
Becky Pashman: Daddy? Daddy, can I eat this left over I just found on the table?
Dan Pashman: Please put that away. I promise at the end you will get more ice cream.
Dan Pashman: At the end of the show, we will reveal which plate made the ice cream taste sweeter. Round/white or square/black? But now let’s get back to my conversation with Charles Spence. He does a lot of consulting for restaurants and food companies, who are very eager to optimize their businesses and boosts profits. That means considering every detail. Like for instance, a restaurants background music.
Charles Spence: If there's classical music playing in the background, you'll probably end up spending more on the wine that we order and on the meal that we choose to eat. Some association between class and classical music, that means we spend more. What we also see is that if you're in an ethnic restaurant then playing the ethnically appropriate music, maybe a bit of opera in a pizzeria, some sitar music in the Indian restaurant, does lead bias people to choose more ethnic food from the menu, than they otherwise do, and also quite often to rate that food as tasting more authentic that it would do if you were just playing top 40 or the duty manager's kind of random Ipod. There's also a work showing that the speed, sort of the tempo, of the music—the faster the tempo, the faster we all walk down the supermarket aisle, the faster we all bring our glass to our lips, the faster we'll bring our fork to our mouth. We kind of have been trained to the beat.
Dan Pashman: You said that Chipotle...
Charles Spence: Mm-hmm?
Dan Pashman: Actually plays faster music during the lunch and dinner rush?
Charles Spence: Yes.
Dan Pashman: What's the purpose of that?
Charles Spence: So you got queues building up, what you want to do is release some of the pressure and by speeding up the music, that will encourage people to come in and leave more rapidly. Whereas, other times of day, when maybe it's a bit slow and there aren't many customers, you might want to keep some there for as long as possible to try and maintain the atmosphere. Under those situations, a slower track will help.
Dan Pashman: And sound doesn't just come in to play with background music. We're also really sensitive to the sounds our foods make when we eat them. Charles has shown in his research that people say one chip tastes better than another when the crunch sounds louder, even though it turns out that the two chips are identical. He says that might be because we associate crunch with fresher produce, which have more vitamins and are less likely to have gone bad. And food brands know that we love that crunch sound. Kellogg’s has spent years refining the precise sound that Corn Flakes make when we bite into them. Charles says companies use this in commercials too.
Charles Spence: From those who, you know, make ice creams with chocolate again, they know that that first crack when you see the model on the screen biting into the chocolate covered ice cream, that's a really irresistible moment if you accentuate the sound of the crack, people will expect to like more the contents.
[NESTLE CRUNCH COMMERCIAL CLIP]
Dan Pashman: The coffee company, Nespresso, has found that when their coffee machines make sharp noises, people think the coffee itself tastes bitter. Soothing sounds make the coffee taste sweeter. Then there’s food packaging, where even the smallest details can make a big difference in profits. Like for example, imagine a can of soup. On the front there’s a picture of a bowl of soup and a spoon. Now, most of us are right-handed, so we prefer to see the spoon on the right side of the bowl as we look at that image, with the handle pointed towards us, as if the spoon’s in the perfect spot for us to pick it up and start eating.
Charles Spence: And now when we see food, our brains straight away get into the act of simulating how would I eat it, how easy would it be to consume, what kind of energy content does it have. And the easier you can make it for the person viewing the package to simulate the act of eating, the more fluent it will be for them and so they'll enjoy the experience, or imagine enjoying the experience that little but more. If you're showing a mug, even. If you have the mug with the handle, that's again kind of tilted to the left, that's gonna be hard for a righty to pick up. And again, that slight increase of difficulty to be imagining myself picking up that cup will translate into a slighter lower liking.
Dan Pashman: But I wonder— this will be your next study, Charles—Do left handed people buy less soup?
Charles Spence: So, yes. You're absolutely right. It is about our next study, in fact.
Dan Pashman: Oh, really? Tell me. Go on.
Charles Spence: Of course, when things are put just in entirely from the super market, there's not much you can do to change the side of the spoon on the front of the pack. But given that a growing number of us are doing more of our shopping online now, we can see a future, not so far away, in which when go online to do your shopping, your device knows whether you're a left-hand or a right-hander. And then the packages you see on the virtual shelves...
Dan Pashman: Really?
Charles Spence: Are designed just flipped to match your hand-ness, and so increasing processing fluency and hopefully, increase the willingness to purchase.
Dan Pashman: Wow.
Charles Spence: The results are, I think, definitely part of the future. And beyond that I think what's on the front of the pack is a really interesting one because the food portrayed on the front of most packaging actually corresponds to about three times the recommended serving size. So you got a real sort of problem here, where the packaging is being used to grab people's attention in. It looks like a great tasty dish and yet, then set the wrong expectations and norms that when actually you get the pour cereals, myself, I'll end up pouring more than I otherwise might, just because of the amount portrayed on the front of the pack.
Dan Pashman: So theres a couple of food innovations that I have attempted to popularize here on The Sporkful.
Charles Spence: Mm-hmm.
Dan Pashman: And I want to run them by you, Charles, and get your take on them, your scientific and premature, if possible. One of them is the cheeseburger with cheese on the bottom. I find that often, especially, with thick cheeseburger, the cheese on top gets lost. I don't really taste it. I like the cheese on the bottom.
Charles Spence: Mm-hmm.
Dan Pashman: Because it lands on my tongue and I think that way I will taste it more.
Charles Spence: Yup.
Dan Pashman: It also creates a seal so that as the juice flows down where the bottom one doesn't turn soggy. And that's why I like my cheeseburger with the cheese on the bottom.
Charles Spence: OK.
Dan Pashman: I think it's better that way.
Charles Spence: Yup.
Dan Pashman: Can you back me up?
Charles Spence: So, yeah. So, I think, it sounds like you're a budding gastrophysicists there, thinking about the sequencing and the layering one's burger.
Dan Pashman: Yes.
Charles Spence: We have been thinking about the perfect burger and how every often kind of the way things layered or served to us is done because it makes them most appealing visually but that doesn't mean, necessarily, it's best for the mouth. Like sushi, it's sort of served with the fish on top. But you go to Japan and you're supposed to eat it, turn that sushi over so the sushi fish lands on your tongue.
Dan Pashman: Of course, they're lightyears ahead of us.
Charles Spence: Yup. There's been another debate in the English presses last few months about some chocolate covered biscuits. And of course, if you've got chocolate covered biscuits in the front of the package in the adverts, you want to have the chocolates on top because that's the luxurious ingredient. But, of course, when you put it in your mouth, you want to turn it over so that the chocolate hits your tongue where the taste buds are. And so there's been a debate how you should eat your—dunk your biscuits and eat them.
Dan Pashman: Wait, so just to be clear though, you think cheese burger with cheese on the bottom is a positive step? Like that's an improvement on the classic burger?
Charles Spence: Yes, and that thinking about once these things get into my mouth, do I get the relevant bits where I want them to be, the tasty stuff on the tongue not smeared on the roof at the mouth.
Dan Pashman: That's right. Well, I want you to know, Charles, that this whole concept of like of flipping things upside down...
Charles Spence: Mm-hmm.
Dan Pashman: So that what lands on your tongue is accentuated.
Charles Spence: Yup.
Dan Pashman: It's something that I have been on about here on The Sporkful for a number of years. In fact, I have called it... I've dubbed it, "The proximity effect".
Charles Spence: Really? Ahh, OK.
Dan Pashman: Yes, because whatever is closest to your tongue, whatever is in closet proximity to your tongue of that flavor is accentuated. That's why when I get a slice of pizza, I fold it inside out, so that the cheese and the sauce land on my tongue.
Charles Spence: Hmm. Ultimately, there's a lot of work to be done and some of it sort of coming out already, partly from some of the food companies that saying many of our everyday food experiences might not be designed optimally for just this very reason. And maybe by doing that, by re-engineering where the taste appears in our everyday foods, we might be able to maintain a rich taste percept that we all know and enjoy with a little bit less of the unhealthy ingredients.
Dan Pashman: So down the road, Charles’ research could be used to reduce the sugar in foods, while still making it taste just as good. But there’s a catch, you can’t advertise that a food has less sugar or people will say it doesn’t taste the same, even if it turns out that the two foods in question are identical. That’s been found in numerous studies. So how can you make food taste sweeter without adding sweetener? Well that brings us back to our experiment.
Dan Pashman: So our experiment is concluded. We got a lot of great results. We're gonna tabulate them. That means...
Becky Pashman: What does tabulate mean?
Dan Pashman: Count.
Becky Pashman: Count.
Dan Pashman: It was a fancy way to say count.
Becky Pashman: OK.
Dan Pashman: OK. So we gave out a lot of ice cream. Thank you Becky and Olivia and Charlotte and Amelia and Evan, for all of your help. You guys did a great job. So can I tell you guys something? Can I tell you a secret now? Now that we're all finished, we got all of our results done.
Dan Pashman: it turns out that both ice creams were the same. It actually is that we're not testing which ice cream people like better. But we had to make them belive that the two ice creams were different from each other.
Becky Pashman: Ohh. So I get it. You were tricking them.
Dan Pashman: In the end we found that people said the ice cream tasted sweeter on the round/white plates than the square/black plates. The white plates had a sweetness rating of 4.6 out of 5. The black plates were just 4.1 out of 5. Now, I know this wasn’t the most scientific study, but it turns out when Charles Spence ran a similar study, he had similar findings.
Charles Spence: The number of hypotheses as to what might be going on there, it could be that our brain kind of keeps track of all the foods we've eaten. Say maybe that there will be more deserts are served on white bowls, whereas more cheese and savory dishes are served on black slate, angular and black.
Dan Pashman: And you say that there's also a theory that there we correlate sharp angles with more bitter flavors.
Charles Spence: Mm-hmm.
Dan Pashman: And round and smooth with sweetness, that there's an evolutionary explanation for that, too. Is that right?
Charles Spence: Yes, only a couple of them, in fact. So sweet things and also born with liking sweet taste. Rounds shapes are more sort of cuddly. Whereas angular shapes are potentially dangerous, a weapon that might hurt us, and will trigger fear circuits in the brain very soon after we see an angular shape. And bitterness is a in a potentially sort of poisonous and so it could just be this kind of um crude separation. If good things go together, like round and sweet. And bad things, like angular and bitter. But it could also be something about the sort of tasting experience, itself, in that when we give people just sweetness in the glass, we experience it coming on ramped up more gently and stays and fades away. Whereas if I give you an acidic taste on your tongue, it will say, "Wow, it was there. It came on straight away. It was really sharp, onset and then it just faded away really quickly." So even in our tasting experience, there's kind of a—some tastes are rounder, like sweet. And some tastes are have a much sort of sharper profile in our experience and maybe that's the link, as well.
Dan Pashman: That’s Professor Charles Spence at Oxford University. His book Gastrophysics: The New Science of Eating was published in 2017, and he has a new book coming out this week, called Sensehacking: How to Use the Power of Your Senses for Happier, Healthier Living.
Dan Pashman: Next week on the show my guest is Julian Castro, former presidential candidate, cabinet member, and mayor of San Antonio. We’ll talk about his support for boycotting Goya, the politics of fighting hunger, and whether he prefers his flour tortillas made with shortening or lard. That’s next week. In the meantime, check out last week’s show with chef and food stylist Elle Simone Scott, we had a great conversation, it’s up now. And while you're doing things on your phone, please follow me on Instagram. See what I'm eating, see what I'm doing. Maybe it'll make you want to eat things, too. On Instagram I'm @TheSporkful.