Twinned spell says:
When you cast a spell....
Ring of spell storing says:
This ring stores spells cast into it, holding them until the attuned wearer uses them. The ring can store up to 5 levels worth of spells at a time.... ...While wearing this ring, you can cast any spell stored in it. The spell uses the slot level, spell save DC, spell attack bonus, and spellcasting ability of the original caster, but is otherwise treated as if you cast the spell.
When I cast a spell from the ring can my Sorcerer apply the twinned spell metamagic, assuming he meets all the other normal constraints?