The rate of formation would depend on the solubility of the solute. So in the case of lipids the solubility is so low in water that formation rate is much faster than say citric acid. I agree normally we would consider ripening to be long term, but when the kinetics are so rapid, who's to say the ripening doesn't happen to some extent in small time periods.
In my mind, I want to know why the less soluble the free lipid is, the bigger the particles. So as long as the particle hasn't stabilised (preventing growth), or when free lipid is available, free lipid will try to find a larger particle to latch onto. So solubility changes only change the rate of formation, allowing for more (or less) time for this brief ripening to occur, resulting in larger or smaller particles.