You are going to have to paint over it.

When I was a teen, I poured myself a glass of purple grape juice and then ran to another room with the glass in my hand. I tripped and my hand jerked upwards, spraying grape juice on the kitchen ceiling. The stains remained until my parents repainted that ceiling.

Something I would like to see some test and report back - food color stains, particularly red and purple seem to be a recurrent problem. I wish someone would get some powerful hydrogen peroxide from the hair dressers and test a spot of food stain. I kept some carpet remnants to do this but before I was able to locate the peroxide someone, aka 'the spouse' tossed my stained remnants.