I opened a young coconut this morning, and the flesh and juice was purplish in color. I’ve seen this posted somewhere before, but I can’t remember if it’s okay or not. I used 1/2 cup of the juice and some flesh. Honestly, it didn’t smell or taste bad, so I’m thinking it was okay. And, I didn’t get sick.
I posted a few months ago asking if purple coconuts were okay to eat, and the overall consensus with a definite “no”. Usually, the water of a purple coconut will taste rancid and not sweet, too, so that’s a good indication that something’s wrong.