Question by Kevin7: What is Miracle fruit?

very sweet

Best answer:

Answer by Ted H
If you have any foodie friends, you’ve probably heard of miracle fruit (Synsepalum dulcificum), a native West African berry that looks like a cranberry, but acts like a psychedelic for your taste buds.

Eat the miracle fruit on its own and it doesn’t taste like much of anything. But let the juices coat your mouth, then consume sour foods — like lemons, limes, goat cheese, beer, vinegar, pickles — and a remarkable thing happens: they all taste sweet. “Beer tastes like sweet juice. Lemon tastes like sweet orange,” Keiko Abe of the University of Tokyo told Discovery News.

The fruit’s effect lasts for an hour, and like other trippy experiences, it’s more fun to do it in groups. So adventuresome eaters seek out “flavor tripping parties” during which people pop a berry, then gorge on all manner of sour foods. Guinness beer tastes like chocolate. Tabasco sauce tastes like “hot doughnut glaze,” as one flavor tripper was quoted as saying in this story in the New York Times.

This week, Abe and colleagues reported the key to miracle fruit’s magic. To figure it out, Abe’s research team used cell cultures to test human taste receptors at various pHs. According to Discovery News:
The key ingredient in the fruit, a protein known as miraculin, binds strongly to the sweet taste receptors on our tongues, Abe reported, but it does not activate the receptors at neutral pH.
When acid is introduced, the miraculin protein changes shape in such a way that it turns on the sweet receptors it is bound to, creating a sensation of ultra-sweet without affecting the other flavors in the food.
After the acidic food is swallowed, miraculin returns to the inactive shape, but it remains bound to the sweet receptor for up to an hour, ready to receive a new acid trigger. The strong binding explains the molecule’s lasting effect.

Abe said the sweet-making power of miraculin was stronger than nearly all other known sweeteners. Given that it’s calorie-free, of course there has been no shortage of interest in developing it into a commercially usable sweetener. Perhaps it will be in Japan, where the production of a purified miraculin extract is currently being sought. As for the U.S., however, a 1974 ruling by the Food and Drug Administration banned the sale of an extract.
http://healthland.time.com/2011/09/28/flavor-tripping-explained-how-miracle-fruit-turns-sour-into-sweet/

The small fruit has the color of a cranberry, the shape of an almond and tastes like a flavorless gummy. But after chewing the fruit and rubbing the pulp against the tongue, the berry, known by a promising name — “miracle fruit” or Synsepalum dulcificum — releases a sweetening potency that alters the taste buds.

About five months ago, a Miami, Florida, hospital began studying whether the fruit’s sweetening effects can restore the appetite of cancer patients whose chemotherapy treatments have left them with dulled taste buds.

“What happens in patients is the food tastes so metallic and bland, it becomes repulsive,” said Dr. Mike Cusnir, a lead researcher on the project and oncologist at Mount Sinai Medical Center. “Most of the patients undergoing chemotherapy have weight loss. Then they cut further into their diet and then this furthers the weight loss. It causes malnutrition, decreased function of the body and electrolyte imbalance.”

One of Cusnir’s patients, Don Blechman, told him about the fruit after discovering it while he and his wife volunteered at a tropical fruit garden in Coral Gables, Florida. Cusnir filed for an investigational new drug application, which is required by the U.S. Food and Drug Administration to use an unapproved product in a new patient population. His study seeks 40 cancer patients.

“The majority have given good feedback that it did improve taste,” Cusnir said. “A few patients felt there wasn’t much change. The feedback is mixed as it usually is in any situation. It’s been encouraging, but we haven’t analyzed the data so far.”
http://articles.cnn.com/2009-03-25/health/miracle.berries.weightloss_1_synsepalum-miracle-fruit-cancer-patients?_s=PM:HEALTH

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