Miracle berry
Synsepalum dulcificum also known as the miracle fruit is a plant with a berry that, when eaten, causes sour foods (such as lemons and limes) subsequently consumed to taste sweet. This effect is due to miraculin, which is used commercially as a sugar substitute. Common names for this species and its berry include miracle fruit, miracle berry, miraculous berry, sweet berry.
The berry itself has a low sugar content[7] and a mildly sweet tang. It contains a glycoprotein molecule, with some trailing carbohydrate chains, called miraculin. When the fleshy part of the fruit is eaten, this molecule binds to the tongue's taste buds, causing sour foods to taste sweet. While the exact cause for this change is unknown, one hypothesis is that miraculin works by distorting the shape of sweetness receptors "...so that they become responsive to acids, instead of sugar and other sweet things." This effect lasts until the protein is washed away by saliva (up to about 60 minutes).
You get to buy it online in form of tablets or freeze dried but no luck finding it in Qatar
Good to know.