By Medical Discovery News
June 2, 2012
As intriguing as its name is, the Miracle Berry’s effect on the tongue is even more fascinating. Minutes after popping the luscious red berry in the mouth and swirling its pulp around, a shot of Tabasco sauce will suddenly taste like spicy doughnut glaze.
The magical little fruit changes the way taste buds perceive certain flavors, especially sour, acidic foods. The cranberry-sized fruit comes from a plant called Synsepalum dulcificum native to West Africa where people have enjoyed its properties for centuries. Yet, until recently, no one knew why it is able to change the taste of sour foods into deliciously sweet treats.
Forty years ago, scientists discovered a protein appropriately named miraculin is the active ingredient in the berry. Though they couldn’t be sure, scientists guessed the protein binds to sweet taste receptors on the tongue, changing the way sour foods taste. A study led in part by Ayako Koizumi from the University of Tokyo not only confirmed this hunch, but uncovered the specifics of the protein’s mechanisms.
Though its chemical properties make miraculin a super sweetener, unlike others, miraculin does not trigger the sweet receptors on its own. In fact, the Miracle Berry has the unremarkable taste of a mild cranberry. Once spread around the mouth, its proteins bind with taste receptors on the tongue, which are bundled into clusters of 50 to 100 to form taste buds. The Tokyo study found that compared to other sweeteners, miraculin binds to receptors more strongly and changes the shape of receptors so that other sweeteners can’t latch on. That’s why aspartame tastes bland after eating a Miracle Berry.
However, when an acid is introduced in the mouth, the sweetness goes through the roof because miraculin itself changes shape by attracting extra protons. This supercharges the sweet receptors, so that oysters with lemon juice taste like chewing gum. Lemon sorbet with Guinness tastes like a chocolate milkshake. And something sweet can taste too sweet or cloying. Once the sour food is swallowed, miraculin changes back to its original shape, waiting for the next acid to come along.
The effect of a Miracle Berry lasts about an hour or sometimes two, but the fruit is expensive at $2 a piece. Its popularity has attracted companies to extract miraculin, purify it, and sell it in tablet form, which works the same way. Although the berry and tablet are available on the Internet, the Food and Drug Administration reviewed but did not approve miraculin as a sugar substitute in the 1970s. Now various groups are petitioning to change this ruling, which they believe was influenced by special interests.
Without a means for wide commercialization, the fruit has become the focus of taste-tripping parties where people pay to try the fruit with everything from goat cheese to beer. But it’s also found a higher calling. For cancer patients whose chemotherapy treatments leave a metallic taste in their mouths, the Miracle Berry can make eating pleasurable again.
Pamela K. Bond 