Standard solution for 54.6? Ermmmmm.....
Well IMO to get the effect item, you'd have to spend 2-3 bombs to try and freeze 1 or 2 fruits on top (lemons and pears) or to smash the blob around.
After this short time, go down while whatever is frozen, is STILL frozen, to make it easier to survive. Time it so that the effect item doesn't spawn while you are on top dropping bombs, or falling beside. Be quick so that you are already inside when it spawns.
This way, you can either get the item, or die very quickly and get it with a shield. OTHERWISE, you would have to jump off the top to kill yourself on spikes below, then reset up top and go with the shield to get the item. There isn't enough time to do it this way.
Recap:
2-3 bombs on top of cage, drop down, be inside cage when item spawns.