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Partial Mash-Full Volume Boil vs. Partial

I have brewed about 7 extract batches now and I am looking to increase the overall quality some more. From reading it looks like partial mash, full volume boils, and better temperature control during fermentation makes the biggest difference. I have a wort chiller now and I am getting a 32qt pot.

My question is, I still will not end up with 5 gallons of wort after the PM and sparge. If I was going to do a full volume boil, is it better to sparge the grains to fill the left over volume? Or is it better to just top the remainder off with water before the boil? Or does it really matter…

My thoughts would be that you don’t want to over sparge the grain. Possible to extract tannins if you do?

I would use enough water to slightly over sparge based on a grain ratio to the beer.

Say you are getting half your SG from grain. I would sparge to a volume of about 3.5 gallons. Based on a 6 gallon preboil volume. Top off with water and add your LME/DME.

You’re on the right track. I would however get a 40qt pot instead of 32qt. You can still boil over in 40qts… I would be nervous with 32qt.

Don’t think a PM is necessary. I would only steep flavor grains (roast, crystal, etc), so sparging wouldn’t be that critical. If you want to fool with a PM some fermentables to get your feet wet, have at it.

IMO, a bigger payoff in quality would be from a full wort boil and fermentation temp control. Be patient and try some software, but it will take some trial and error to dial in a full wort boil. Also, check and see if you have places with good stable ferment temps so you don’t need to get a fridge or t-stat control yet.

[quote=“Nighthawk”]My thoughts would be that you don’t want to over sparge the grain. Possible to extract tannins if you do?

I would use enough water to slightly over sparge based on a grain ratio to the beer.

Say you are getting half your SG from grain. I would sparge to a volume of about 3.5 gallons. Based on a 6 gallon preboil volume. Top off with water and add your LME/DME.[/quote]

I thought tannin extraction was from high PH and/or sparge temp being too high.

Thanks for all the advice!

I live in FL and in the next few weeks the temperature in the house will be fluctuating so much that i will pretty much have to use a t-stat. We have an extra fridge now so it will be a pretty small investment.

So you think that a full volume boil is a better benefit than partial mashing?

Yes, IMO a full wort boil is better benefit than PM.

You gotta chiller or a way to cool your full wort boil? Also don’t rush to pitch yeast in a warm fermenter. ALWAYS pitch at or below ideal ferment temp.

I am doing my first partial mash full volume boil this weekend. This will be my 2nd PM, and 1st full volume boil. I just upgraded from a 4 gallon kettle and stove top, to a 10 gallon mega pot and banjo burner.

My questions is: what boil volume should I top off to after my sparge? My goal is to yield 5 gallons and hit my OG after a 60 min boil. I know that each system is different, but where should I start?

6 gallons? 6.5?

Thanks in advance!

Congrats on the upgrades. You will find it was well worth it!

It takes a few tries to tweak this but you’re not far off at all. Do yourself a favor and makes some notes when you begin this it will payoff in the future. I strive for 5.5G to the fermenter (fermenter is 6.5G) and I typically start with around 7G at the beginning of a boil. I have a 200K kajun kooker though. Always a 60 minute boil for me unless it is a huuge beer. No more than 90 though. The trick for me was keeping an eye on it with a wooden brew spoon with notches on it every gallon with a double mark at 5.5G.

If it were me I’d try 6G this time. Resist the temptation to top off if you go lower and enjoy a more potent product. Unless there is some odd reason like high winds you shouldn’t be far off. Review what you did and make note for next time.

Be sure to cool it down ASAP to under ferment temp before pitching yeast.

6.5-6.7 gallons pre-boil will get you down to about 5 gallons in the fermenter.

I usually shoot for 5.25-5.5 gallons in the fermenter. You lose quite a bit of beer to all of the trub in the bottom of the fermenter.

You might want to consider picking up some brewing software as you get more serious. It will do a lot of the calculations for you. I use BeerSmith and really like it.

Thanks for the input!

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