I've been eating fruits from the Myrciaria vexator trees (blue jaboticaba), and notice that although they appear to have reached full coloration, and peak ripeness. they are still not ready...after about 8 days...fully purple...still not ripe!
They need to have a definite rubbery give when squeezed, to be considered ready, and after turning fully purple, it can take almost 2 weeks to reach this stage.
I've let a few people taste the fruits, because they saw them on the trees...and begged to eat them...I warned them that they weren't ripe yet, but based upon the fruit appearance they insisted...and the result was a disappointment to the eager consumers. It's something like eating a sapodilla too early...the taste is horribly tart, tannic, and astringent.
When they are ready, the texture is divine, the flavor is outstanding...the fruits are quite large, but so is the seed, and the skin is thick, and tannic (its best to avoid biting right into the fruits, so use a knife to cut them in half, then consume).
This tree is one of my favorites, but you must understand the tree to enjoy the fruits. The same is even true for the common Sabara (M. jaboticaba)...many people eat them too early, never getting a chance to enjoy the true delicious sweet flavor, and silky smooth texture of a properly ripened jabuticaba.