Going BIG. What are your techniques to push your system’s capacity?

[Qualia]

G’day.

For a while now I have been pushing my system (2 vessel HERMS, Keggle w’ 30L cooler) to brew 40L batches by boiling high gravity worts that are then topped up with 8-10 litres of boiled water to bring the OG down to target.

I’ve even floated a pot in the BK to top up the first run with some BIAB wort.

Is there any noticeable decrease in quality using this technique?

How do you GO BIG on brew day?

Cheers.

 

[Reg Holt]

My understanding is that the commercial brewers ferment their high gravity wort and then dilute to the ABV they are looking for. For a home brewer you will then have the problem of fermenting a high gravity wort, in regards to how much oxygen, how much yeast. Reiterated mash will come up with the same problems, but get it right and and you can increase the volume of beer from one brew day.

 

[Qualia]

Hey Reg,

Interesting. I add my top up before fermentation. Know of any pros/cons about doing it before or after?

 

[Reg Holt]

As I suggested the pros and cons are, fermenting a high gravity beer is not beyond a home brewer, though I would add one word, "experienced" The thing is if you don't try you don't learn, the commercials do it because of fermenter space, a few hours mashing and brewing is fine, days in a fermenter is not. All comes down to dollars. For the home brewer faced with fermenting a big beer is the amount and viability of the yeast? How much oxygen to add? How do I know how much oxygen I have added? to much and the yeast suffer to little and the yeast suffer. When do I add the oxygen? All this is not insurmountable, (would be a good topic on its own) will all come down to experience.
Read up on reiterated mash that may help.

 

[Qualia]

Good idea about reiterated mash. Might use that technique for something a wee stronger. Article here if anyone else is interested: http://beerandwinejournal.com/reiterated-mashing-1/

 

[enoch]

G’day.

For a while now I have been pushing my system (2 vessel HERMS, Keggle w’ 30L cooler) to brew 40L batches by boiling high gravity worts that are then topped up with 8-10 litres of boiled water to bring the OG down to target.

I’ve even floated a pot in the BK to top up the first run with some BIAB wort.

Is there any noticeable decrease in quality using this technique?

How do you GO BIG on brew day?

Cheers.

I did 45 from a 30ish litre Grainfather that way until upsizing. No issue I could see.
If you want a safe boil near capacity then use fermcaps to control boil overs. Don’t get too adventurous on the levels till you see how it works. On my brewzilla with fermcaps it still wells up by 5cm with bubbles in the wort but no foaming then periodically drops.
It was a BIG surprise first time I saw it as I thought it was about to go!

 

[goatchop41]

Hey Reg,

Interesting. I add my top up before fermentation. Know of any pros/cons about doing it before or after?

If you plan on doing it after fermentation, then you will have to take as many steps as possible to ensure that O2 ingress is kept to a minimum - this will include boiling the absolute crap out of the water to deoxygenate it before adding it. Bigger commercial breweries obviously have the equipment to be able to do this and keep DO to a minimum, whether or not you could do it successfully at home is another question.

I personally don't see the point of liquoring back after fermentation - you have to worry so much about O2, as well as the fact that when fermenting a higher gravity wort, you have a greater chance of formation of esters, etc. If you want a fairly clean beer, then it will be tough and you'll have to be pretty much perfect with yeast pitch, fermentation profile, etc.
It would be much, much easier to liquor back prior to fermentation.