Freezing Under Mashed Beer

[TrevVB]

So my buddy brewed some beer two months ago with some friends to show them the process. Rather than let the mash sit the whole hour, he mashed only 30mins, brewing with some week wort. No idea on his gravities, he "just knows it will end up beer". So after kegging and carbing the beer, it is weak in the maltiness (it's a pumpkin pie brown ale).
Now I am in possession of his beer (he is deploying for a few months), and I was thinking of dropping carb and freezing it to remove some water, increasing the intensity of the maltiness and abvs. What are your suggestions and experiences?

 

[Travestian]

What you are talking about is actually making something like an ice beer. You won't be reducing just the water content though. Some of the sugars and other flavor bits and hence the maltiness will be going with it. Really all you'll be doing will be increasing the alcohol content by a little.

 

[TrevVB]

Thats what I was afraid of. I thought of icing it and then boiling the ice I removed and add it back to retain the sugars and maltiness.

 

[masonsjax]

I have done this. Its like jacking cider. If you freeze the beer solid and let it drain into another container, it will intensely concentrate the flavors, and yes, increase the alcohol content. If you repeat the process a few times, you'll end up with a 30-40% sipper that will be very intense in flavor, like a very rich strong barleywine. I usually start with a full 2 liter soda bottle and end up with about a quart or less of turbo beer.