I had some strong black vine brew in the fridge for a month or so once, it turned, and mold/bacteria/something grew inside it. This was after sterilizing a glass bottle (12oz canada dry ginger ale, plastic soda cap) by submersion in boiling water for 5 min, then boiling my brew hard, then a quick microwave boil after i bottled it. Let it cool, then threw it in the fridge and forgot about it.
A month or so later, i was going to drink some with a mushroom chocolate i was gifted, and it smelled awful, and had floating chunks of whatever the hell that stuff was. Down the drain it went. I was pretty cheezed too, worked hard (3 day crock pot brew/reduction) and it was a few strong doses of caapi, was filtered 3x with a buchner funnel, real good brew/vine wasted.
Long story short, freeze it. Its too easy, rather than risk it turning/going bad in the fridge.