Damn... I was gonna venture a guess and glad I didn't lol... Weezard, that's pretty genius and likely spot on... +1

I was gonna suggest that since your fridge probably like most fridges and frost cool via an adjacent freezer it can build small amounts of condensation... I was curious if you have it in a jar or out in the open...

but, your specific question on loss of the green tint is most likely perfectly answered above

//on a side note, I've never made oil that way... link to a good method to follow/directions? Thanks in advance!