Is almost a full boil ok?

[Andysam]

Would there be any differences in boiling 8 gallons of wort for a 10 gallon batch? This way, I would boil 2 gallons of water say the night before to sterilize them, put them in sanitized 2liter bottles and freeze them. Then at the end of the boil of the 8 gallons, I would cut out the ice and put the ice cubes in the boil kettle.

This way I would cool the wart very fast. I would also not have to be as concerned as I am now about boiling over in my 15 gallon pot.

But would this effect the taste or structure of the beer at all?

I am doing all grain

 

[Yuri_Rage]

Two gallons of ice in a ten gallon batch isn't going to go very far in lowering the temp.

 

[samc]

You should not be worried about boiling over a 15 gallon pot. I routinely boil 14 gallons of wort in my keggle without any boil overs. When it gets close to boil I skim foam/crud and stir until the danger is past. If you are doing 10 gallons, it's not 8 + 2 as you have not accounted for the boiled off wort and loss due to trub & hops. Partial boils do change the recipe.

 

[Andysam]

You should not be worried about boiling over a 15 gallon pot. I routinely boil 14 gallons of wort in my keggle without any boil overs. When it gets close to boil I skim foam/crud and stir until the danger is past. If you are doing 10 gallons, it's not 8 + 2 as you have not accounted for the boiled off wort and loss due to trub & hops. Partial boils do change the recipe.

Yes, that is why I am worried about boiling 13-14 gallons in a 15 gallon pot

 

[scinerd3000]

if you use less water for the boil, you will inevitably have a higher gravity when you toss in the hops. The higher the gravity of the starting wort the less alpha acids will be contributed by the hops leading to less IBU's in the finished beer

 

[Andysam]

if you use less water for the boil, you will inevitably have a higher gravity when you toss in the hops. The higher the gravity of the starting wort the less alpha acids will be contributed by the hops leading to less IBU's in the finished beer

Thanks, now that is a good reason. I love my IBU's!

 

[Yuri_Rage]

Ok, here's some more data for you: I use 60 lbs of ice MINIMUM to recirculate icewater through my chiller when cooling 10 gallons of wort from boiling to room temperature.

16 lbs, even when added directly, will pale in comparison.

 

[Funkenjaeger]

Also remember that 8 gallons of wort pre-boil is going to be 7 or less post-boil (depending on your brew kettle) so that's even MORE water you'd have to add at the end.

Also, the less wort you can collect for a given batch size, the less efficiency you can achieve.

You shouldn't worry so much about boilovers. Skimming/stirring/spraying can handle it, or you can do what I do and use foam control drops - then you have nothing at all to worry about.