Any advantage to full boil v. partial boil?

[brewIPA]

Just wondering, for now I am doing partial mash brewing and will be buying a 9gallon brew pot. Is there any difference in quality by doing a full boil over a partial boil? I remember reading that there is a difference in color of the final beer, also that you have to make some adjustments in hopping (possibly malt extracts too I cant remember) if you are going to do a full volume boil. If someone could clear this up that would be awesome, thanks.

Side note, can someone explain specific gravity.. I get the basics, it's the density of wort with sugars versus the density of water. Does that mean all final gravities going to be around the same (because all sugar has been "eaten" by yeast and its going to be close to the specific gravity of water)?

 

[BargainFittings]

Denser wort concentrations extract less hop bitterness so a full boil will save you a bit on hop usage.

Another benefit of full boil is you know that your wort is sanitary from the boil. Unless you top up with pre boiled and then chilled water.

The color of your beer will be lighter with a full boil.

Your final gravity is dependent on several factors including yeast health / attenuation, the percentages of specialty malts and the beginning gravity of your wort.

 

[Pelikan]

^^ What he said. In general, you want to do a full boil if you can swing it.

 

[williec30]

here is a good thread talking about full boils...

 

[brewIPA]

Awesome, thanks guys. Anyone have a thread on SG though, I would like to know exactly what I'm doing on my first brew day (when I get back to flagstaff ~ a week).

 

[VTBrewer]

Depending on the yeast and your attenuation, you'll probably find your final gravity to be about 1/4 of the OG. So a 1.060 will finish at around 1.015.

 

[brewIPA]

Actually one quick question, how large of a brew pot do i need to do a 5gallon full boil? I've heard you need like 6.5 or 7 gallons to account for evaporation, so would a 9gallon (what I was planning on getting) work, or should I get a 10 or eleven? And if I do get a 10 or 11 should I get a burner, or will I still be able to brew stovetop. Thanks.

 

[VTBrewer]

I have a 9 gallon pot and can get a full boil when i put it over front and back burner. In warmer weather I brew outside. Maintaining a rapid boil is rather important.

On the stove I lose about one gallon per hour of boil. Outside can be significantly more, especially in lower temps.

 

[Pelikan]

Bear in mind that for a 5ish gallon batch, your boil is going to need to be about 6.5 gallons to account for boil-off. Unless you have a Viking, getting that much wort to boil on a stove is pretty hard.

I split my boil into two mini batches of ~3.25 gallons each. Just half your ingredients and distribute them between two 20ish quart pots, then recombine in your fermenter afterward.

 

[Grinder12000]

I split my boil into two mini batches of ~3.25 gallons each. Just half your ingredients and distribute them between two 20ish quart pots, then recombine in your fermenter afterward.

That is what I do on the electric stove - two half boils. NOW I have a big mofo cooker in the garage waiting to be used (must clean garage AND get above 0F). I have a 7.9 gallon Brew pot - hope i's big enough.

 

[Yooper]

If you're unsure if your stove can boil that much wort (and most can't), then try it with water first. A rolling boil is important, so that you get the isomerization of the hops oils. If you can't maintain a boil of 6 gallons, then do the largest size boil you can. Even a 4 gallon boil gives better results than a 2.5 gallon boil.

One other thing that may not have been mentioned is to make sure you take the lid off the pot during the boil. You want the bad stuff to escape via vapors. So, if the only way you can boil that much is with the lid on, then make the boil smaller.

I do boil inside on my gas stove, but I have a big kick ass burner on my stove (like a generic Viking) and even that takes a fairly long time to get to a boil. If you have an electric stove, though, there are some things you can do. Flyguy has a thread on insulating the brewpot so that you can get a boil easier on an electric stove. I'll see if I can find it.

 

[jharres]

And if you are unfortunate enough to have bought one of those cool ceramic stove tops, don't even try a full boil, cause it won't work. I can keep a rolling boil on 3 to 3 1/2 gallons by using the front, back and bridge elements, but that is about it. Much more and I can't sustain a good rolling boil.