DEBBIE ELLIOTT, host:
This weekend Washington, D.C. is showing its softer side. The city's cherry blossoms are erupting into pale pink bloom. The display is the legacy of David Fairchild, the botanist with the U.S. Department of Agriculture who introduced 20,000 exotic plants to this country. In 1910, he asked Japanese officials for the original shipment of cherry trees. A few years later he traveled to West Africa and brought back a magical berry. The miracle fruit, as it's called, does an amazing thing to your taste buds. You pop one into your mouth and the next thing you eat tastes sweeter. A lemon becomes lemonade. A bologna sandwich, cake. Adam Leith Gollner is currently writing a book about miracle fruit. And he joins us from the studios of the CBC in Montreal.
Mr. ADAM GOLLNER (Writer): Hello.
ELLIOTT: So scientists have been studying just how miracle fruit works its magic on our tongues. What have they been able to figure out?
Mr. GOLLNER: Well, basically after you eat the miracle fruit and the pleasant squirt of juice coats your tongue, that juice contains a fascinating protein called miraculin. It sounds like something out of Superman.
Mr. GOLLNER: Yeah. Miraculin is basically this protein that has some little sugars attached to it. And those sugars are just out of reach of the sweet receptors on your tongue. So what happens is that in a kind of biochemical quirk the sweet receptors keep trying to get a hold of those sugars, almost like a donkey who keeps trying to bite a carrot. But only when you eat a sour food, like a lemon, can the donkey suddenly grab the carrot. The sugar molecules pop into the sugar receptors, which send sweetness signals to your brain. And you start tasting sweetness.
ELLIOTT: Does it make all foods taste sweeter?
Mr. GOLLNER: No. No. It only makes sour foods taste sweeter. So the key that unlocks our taste receptors is sour food.
ELLIOTT: So things like lemons, limes, pickles.
Mr. GOLLNER: Yeah. Pickles taste like honey after eating a miracle fruit.
ELLIOTT: No way.
Mr. GOLLNER: Way.
ELLIOTT: That is weird. So describe for me the miracle fruit.
Mr. GOLLNER: Yeah, they're these little red berries that are kind of like the size of a small olive or maybe the tip of your pinkie.
ELLIOTT: Where do they grow?
Mr. GOLLNER: They grow in West Africa in what was known as the Gold Coast. And traditionally they used it before eating some of their foods like porridges and breads and fermented palm wines that are shockingly sour. These days it isn't used too often because it's not really cultivated on any scale. It grows in very inaccessible parts of the rain forests. And so they use it as a novelty item or a parlor trick. Little kids love it. They take it before partying.
ELLIOTT: It sounds like this could be a great trick to use if you were trying to lose weight or for people who had to curb their sugar intake because they were diabetic. Has anyone in the United States ever tried to market miracle fruit in this way?
Mr. GOLLNER: Yes. There is an amazing story that goes back to the 1960s. The U.S. Army and the international pharmaceutical industry figured out how the molecule works, how miraculin works. And this young visionary named Bob Harvey started a company that figured out how to synthesize miraculin, and he had millions of dollars invested and plantations all over the world. And he had developed products like a miracle fruit popsicle that was coated in miraculin so your first licks would be of the miracle fruit. And then the rest of the popsicle would taste really sweet, and miracle fruit chewing gum and miracle fruit soft drinks.
And all of this stuff was 100 percent sugar-free. But before getting regulatory approval they started testing it on little kids, who loved it. But the FDA decided that it hadn't been proved to be safe, so they didn't allow it to be marketed as a food additive.
ELLIOTT: Well, we found a man named Curtis Mosey(ph) in Fort Lauderdale who grows miracle fruit in a nursery near his home, and he sent us a few berries to try. So we're going to say goodbye to you now, Mr. Gollner. Thanks for talking with us.
Mr. GOLLNER: Thank you, Debbie.
ELLIOTT: And now the proof is in the pudding, as it were. I couldn't try these thing without some backup. And who better than Susan Stamberg and Linda Wertheimer, who have some of the best taste buds at NPR.
Now, this is a little bit complicated. I'm going to hand each of you two of these berries from the miracle fruit. Two for you, Linda, two for you, Susan. I'm going to take two.
SUSAN STAMBERG: They're beautiful. Look at, they're sort of terra cotta.
LINDA WERTHEIMER: They look like little beans.
STAMBERG: Yeah. They're lovely.
ELLIOTT: And if we put them in our mouths, we get the juice from them. We let that go over our tongue.
ELLIOTT: And then we can spit out the seed.
STAMBERG: Both together. Yes, here we go.
ELLIOTT: Hmm. Now, we are going to start with lemon.
ELLIOTT: I'll give each a lemon.
STAMBERG: Each of us, we suck a lemon and we will be able to...
ELLIOTT: And we'll suck and see what happens.
STAMBERG: ...play our trumpets later, you know.
WERTHEIMER: Oh my goodness.
ELLIOTT: This is like lemonade.
WERTHEIMER: The lemon bites your tongue, but the taste registers as sweet.
STAMBERG: How very strange.
ELLIOTT: A scientist who works with these miracle fruit berries tells us that you can actually eat these berries and then eat a bologna sandwich and it tastes like cake.
WERTHEIMER: What a dreadful idea.
STAMBERG: Thank you for not asking us to try that, Debbie.
ELLIOTT: You're welcome. Let's find out what it does to cheese.
ELLIOTT: We have three types of cheeses here. I'll let you choose what you like. There's cheddar, smoked gouda, and a dill havarti, I believe.
WERTHEIMER: Boy, you weekend people know how to live it up.
ELLIOTT: We know how to eat on this show.
WERTHEIMER: Yes, you do.
STAMBERG: I'll take the cheddar.
WERTHEIMER: Okay, dill for me.
ELLIOTT: I'll try this, the smoked gouda.
STAMBERG: This tastes very cheesy to me.
WERTHEIMER: Yeah, me too.
STAMBERG: Maybe it has to be sour.
WERTHEIMER: Yeah, to be converted.
STAMBERG: To be converted to sweet.
WERTHEIMER: But anyway, thanks for the cheese. Very nice.
ELLIOTT: You're welcome.
STAMBERG: Got any wine?
ELLIOTT: Okay, last taste here. What will the miracle fruit do to coffee?
WERTHEIMER: Okay, you go first on the coffee.
STAMBERG: It sweetened the coffee. Here, drink, because I don't like sweet coffee.
ELLIOTT: It does sort of take the bite off.
WERTHEIMER: It does. Weird.
ELLIOTT: It does.
STAMBERG: It's a miracle.