Rainbow grapes revealed
Yes and no. Rainbow grapes do exist, but they are just regular grapes photographed in a ripening stage known as Veraison, or the ‘beginning of ripening’.
When grapes go into the first stage of ripening, the young immature grapes have a very dark-green colour and a very hard texture, like little rocks, - said Larry Stone, master sommelier and restaurateur. Later, the skin changes its colour. White grapes go from a dark green to a yellowish green colour, and get more and more transparent. Red grapes go from a green to a red colour, the shade of red depends on the variety of grape.
At the end, when they are ripe, all grapes of a particular variety display the same final colour. That is why you can not buy or eat Rainbow Grapes, but you can witness their beautiful transformation.