Maximum Top Up

[Gold_Robber]

Hello all,

I usually brew 3 gallon batches (post boil), but in my new location the stove sucks and wont bring my full kettle to boil. I need to break up the wort into smaller boil batches. Even then, I wont have enough wort. My question is, how much can I top up post boil to bring my gravity to the desired amount? Is 50% top up too much, even if I have all my gravity number in place? Does it negatively affect the beer? Does it matter at all if I reach my post boil gravity number? Thank you.

 

[BrewnWKopperKat]

If you are brewing extract+steep (or partial mash), "partial boil with late additions of extract / water" is a well known process. For a 3 gal batch, you would be boiling around 1.5 gal of wort.

Brewing 'all-grain', I'm not aware of much discussion on boiling a concentrated wort (say OG 100) then reducing it to desired strength (say OG 50). About a year ago, I brewed an Amber Ale with a OG 70-ish wort, then reduced it to OG 45-ish in the fermenter (60 min boil, roughly 1.5 gal wort at end of boil and 1 gal of 'top up' water). The beer came out fine, but I haven't made time to rebrew it or try the approach with other styles.

 

[Gold_Robber]

It is all-grain. I should have put that in my original post. My bad.

 

[Gold_Robber]

It is all-grain. I should have put that in my original post. My bad.

@Yooper I know you are an expert brewer. Can you chime in please?

 

[hamachi]

I do all-grain MIAB brewing using 3 pots on my kitchen stove for the boil. I can do full-volume 2.5 gallon batches or ~ 3/5 volume 5 gallon batches which I then top off in the fermenter. I have not noticed any difference in quality between my full volume and topped-off batches. Based on this, I'd say 50% top up is not too much.

 

[BrewnWKopperKat]

@hamachi : what styles of beer do you brew this way? Are you able to brew high ABV & high IBU styles (like barley wines & DIPAs) this way?

 

[hamachi]

@hamachi : what styles of beer do you brew this way? Are you able to brew high ABV & high IBU styles (like barley wines & DIPAs) this way?

No way would I try that -- as much because of all the wet grain I'd have to deal with as anything else. (My MIAB setup is based purely on muscles and gravity; no pumps, no pulleys.) Given the limited amount of pre-boil volume I can handle, the efficiency would probably suck as well.

I do brew high ABV styles like barleywines and quads (I don't much like high IBU styles). But I only do them in the 2.5 gallon batches for which I can do full volume boils. Looking back at my records, the highest gravity for which I have done a partial boil 5 gallon batch is 1.076, but 1.050 and below is more typical.

 

[BrewnWKopperKat]

Getting More from Less: Three Beers from One Batchthe highest gravity for which I have done a partial boil 5 gallon batch is 1.076, but 1.050 and below is more typical.

Thanks for the insight.

After finishing the batch that I mentioned in #2, I came to suspect that people do this for lower OG beers, but don't talk about it (much) in forums.

Related, but slightly off topic, Three Beers from One Batch (link) may be an interesting read for those who are willing to split / blend wort (with multiple containers).