In the sentence "If you store the spheres in water, osmosis will cause water to flow into
the sphere, while taste and aroma molecules flow out of the sphere." There is a slight misinformation.
osmosis will cause water to flow into
the sphere - that is correct (however not in this case)
while taste and aroma molecules flow out of the sphere - the particles' flow outwards would happen due to diffusion(as osmosis is just the movement of solvent).
Reasuming, the loss of flavor would happen just because of diffusion. Osmosis would make the spheres grow

.