This is part 4 of the series, Food for Thought (And for Eating), about science in the kitchen.
Imagine mistaking vinegar for apple juice, Guinness for a chocolate milkshake, pure lemon juice for lemonade, Jose Cuervo for real tequila. According to those who have tried it, this is exactly what happens after you eat a small red berry called miracle fruit.
A protein called miraculin that is found in miracle fruit is responsible for this gustatory confusion. After exposure to miraculin, tastebuds perceive sour or acidic foods as sweet. The effect lasts for an hour or two. The exact mechanism by which miraculin accomplishes this bizarre feat is still fairly mysterious. It likely involves the protein binding to taste receptors in the mouth and distorting their shape in such a way that they are activated by sour, acidic food.
Miraculin could be useful for dieters or diabetics who are unable to eat sugary food – it provides a way to eat something sweet without actually eating something sweet. But prospective commercial applications of miraculin as a sugar substitute were crushed when the FDA classified it as a food additive in the 1970′s. This classification meant that miraculin would have to pass expensive tests and meet rigorous requirements before it could be used in food sold to the public.
More recently, miracle fruit has gained popularity among hipsters who attend ‘flavor-tripping parties’ where a variety of foods are tasted after eating miracle fruit. There aren’t any known health hazards associated with eating the berry, although miracle fruit “hangovers” have been reported where excessive consumption of acidic food while under the influence of miraculin has led to an upset stomach and mouth sores the next day. So remember, if you do decide to give miracle fruit a try, that glass of vinegar may taste like apple juice, but it’s still a glass of vinegar.