Adiel,
Whether Rollinias come true from seed depends on the origin and neighborhood of the tree. A tree that originated from several generations of self-pollinated trees
could be expected to vary only slightly from the mother tree.
If the tree comes from an area with appreciable Rollinia diversity, than noticeable variations in the offspring are to be expected.
My two trees are the result of my hybridizing a small, sweet, bright-yellow Biribá from Manaus, Brazil, with an unattractive mottley-colored, very pointy, slightly bitter, mucusey, HUGE one from Perú. The offspring from my seeds would vary quite a bit.
Anikulapo,
I agree with your preferences for eating Biribá. If the fruit is chilled it shouldn't be for much more than 12 hours, as it will soon become mucusey and less flavorful.