Do I need to freeze this puree and syrup? Related questions: What causes a cake to sink in the center? and How can I get the maximum flavor from orange peels?

I ended up simmering the zest of 6 oranges (peeled with a vegetable peeler, so there was still a small amount of pith) without rinsing at all. When they were tender, I added the supremed segments of those oranges and simmered the everything for another half hour. I strained the syrup and gave the solids a bit of a whir in the food processor. 

I have just enough puree for one more cake, and this lovely orange syrup. I used a lot of sugar. I can't guesstimate how much sugar because I just kept adding it until I got the level of sweetness I want, but the viscosity of the strained syrup is like Aunt Jemima pancake syrup. 

I'll bake the cake again in 3 or 4 weeks. Will the puree and syrup last that long in the fridge? Or should I freeze it?
It has been said:


  Better safe than sorry. You haven't measured the absolute sugar or acidity levels. Freezing it will do no harm. –  SAJ14SAJ Jan 29 at 1:47


I'm definitely not an expert with baking, but I've worked with fruits in other contexts. The only time I would be worried about freezing would be if I added oil, like for a marinade or such. In your context I think freezing is fine, and sounds like it would be a convenient way to make larger batches to reuse throughout the year.

PS: That puree sounds awesome, I might have to try that to marinate some chicken or pork chops!