Discoloration is due to a compound in beets called betanin, which is what gives the vegetable its red pigment. Some people have difficulty breaking down this pigment. After you consume beets, betanin travels through the body and eventually makes its way to the kidneys.

Why do beetroots appear red?

Beetroots are root vegetables that appear red because the vacuoles in their cells contain a water soluble red pigment called betalain. These pigment molecules are too large to pass through membranes.

What is the red colour in beetroot?

The red beetroot (Beta vulgaris L.) is a good source of red and yellow pigments known as betalains. Betalains consist of betacyanins (red) and betaxanthins (yellow). The major betacyanin in beetroot is betanin and accounts for 75–95 % of the red pigment (Von Elbe et al.