What each one does
Freezing concentrates everything into the shrinking unfrozen phase and forces chains together, which drives both retrogradation and syneresis. Materials that resist are those whose chains cannot easily reassociate: chemically stabilised starches, and gums whose structure is irregular enough to prevent ordered packing.
What decides it
How many cycles the product really meets and how visible weeping would be. A product in an opaque tray tolerates what a product in a clear pot does not.
Where the obvious answer is wrong
The obvious answer is to test one freeze and thaw and declare the formulation stable. Real distribution is rarely fewer than three, and most freeze thaw failures are formulations that passed a single cycle test.
