I have only tried the approximately walnut-sized kernels, of which there are usually 3 to 4 in a fruit. They contain a lot of water and have a subtle, coconut-like, sweet taste.
The fresh, yellow fruits still taste astringent. Only in the brown, overripe fruits are the tannins degraded and the honey-sweet, caramel-like taste dominates.
The fibrous tissue surrounding the seeds can be eaten raw, roasted or cooked at full maturity. It’s said it tastes like coconut.
The jelly palm has delicious orange fruits with a seed that looks and tastes like a mini coconut.
The paper-thin skin hides a very firm, crunchy, yellowish-white flesh, which tastes very good when ripe and has an aroma reminiscent of mango, lychee or (remotely) durian.