The Miracle Berry (Synsepalum dulcificum), when eaten, causes sour foods to taste sweet. This effect is due to a glycoprotein called miraculin and can last up to 30 minutes. The Miracle Berry originates in tropical West Africa.

It never got approved as a food by the FDA (US Food and Drug Administration). Without FDA backing, it’s legal to buy whole berries, or powdered ones, and to sell them in a restaurant or cafe, but you can’t distribute miraculin containing products in the US.

The circumstances surrounding this seem to be a story of mystery and intrigue, involving people being followed in a car, stolen research files, an FDA commissioner who accepted a bribe, alleged sabotage by the sugar industry and Donald Rumsfeld.

Also worth mentioning, there are “flavor tripping parties” featuring the miracle berry.

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