Top up liquor to boiler or fermenter

[DemonBrew]

Say you get less boil volume from a mash but at a higher gravity.
So you need to liquor back to get correct volume and gravity.

What's opinion on whether to add liquor to boiler pre-boil or add to fermenter pre-ferment?

[JLL]

Definitely in the kettle to avoid possible contamination. Even adding at post boil prior to whirlpool would be fine.

[DemonBrew]

Definitely in the kettle to avoid possible contamination. Even adding at post boil prior to whirlpool would be fine.

Common practice in the UK microbrewery scene seems to be in the FV pre-ferment.
I normally add to kettle though have adjusted in the FV.
Would prefer to have full boil volume.

Other thing to consider is PH of the wort in either case however?

[DemonBrew]

Suppose it's for expediency, adding to fermenter pre-ferment to make sure to get final production volume?

Concern about contamination is largely taken care of by UK water quality, sanitised hoses etc.
More concerned about PH of wort/final beer with any top-up method.

Anyone have any other comments?

Cheers

[Beer_Nut]

What you are describing is known as Gravity Brewing or High Gravity Brewing. It is very common in small breweries that want to squeeze extra volume out of a brewhouse. I worked for a brewery who did this all the time. We had a 10 bbl brewhouse and would fill 30, 40 and 60 bbl fermenters with it. We would heat the water up to 80 C and add it to the whirlpool. We would adjust the hop additions for the larger volume and we would also treat the water the same way we would for mashing/sparging. We were able to increase volume by 40%, we were knocking out 14bbls of wort. We could only obviously do this on the lower alcohol beers. You may or may not have to adjust your pH, it all depends on how hard your water is.

[TGTimm]

Generally, de-gassed water is used for topping-up in high gravity techniques. If you use 80+C H2O from your hot liquor system and add on the hot side of the HX (whirlpool, kettle), you're effectively getting de-gassed H2O. De-gassing towers for addition on the cold side are big and expensive, but many breweries prefer to do it this way. Microbial filtration or UV sterilization is also needed for cold-side addition. You can probably get away with skipping the de-gassing and sterilization, at least most times, but the cost of dumping a fermenter....

[kcolby]

Generally, de-gassed water is used for topping-up in high gravity techniques.

I'm interested in the rationale behind degassing prior to introduction to the Fermenter. From my perspective, it seems like adding clean, cool, sterile water to the fermenter simply means that your DO2 in the wort would need to be measured or your calculations/estimates would be off. Beyond that, I'm having difficulty in thinking of what else might cause issues. I am making the assumption that the top-up is done essentially pre-fermentation rather than post fermentation. Post fermentation you would obviously want de-oxygenated water at a minimum to prevent the top up as a source of O2 in the finished beer.

Please tell me where I'm wrong and perhaps the flaw in my logic, Thanks!

[TGTimm]

I think you caught me out there. The de-gassed water is used post-fermentation, to achieve a uniform ABV. Still, oxygenated water on the cold side complicates the process of getting your DO2 at the desired level for fast yeast growth without generating oxidized flavors. A good DO2 meter combined with O2 addition in the fermenter (we add O2 in-line at castback) would solve the problem.

We run multiple brewhouse batches per fermenter, so we adjust overall gravity by adjusting the gravity of each batch--if needed. This isn't exactly simple, either, but it's the way we do it.

[kcolby]

I think you caught me out there. The de-gassed water is used post-fermentation, to achieve a uniform ABV

That certainly makes sense then! I'm glad I wasn't overlooking something obvious.

We run multiple brewhouse batches per fermenter, so we adjust overall gravity by adjusting the gravity of each batch--if needed. This isn't exactly simple, either, but it's the way we do it.

I would expect that it would make the most sense to correct the brewhouse batch rather than the final fermenter contents. It may take a little longer to get it right on the hot-side on each batch but seems like it would be a little more consistent.

[TGTimm]

I would expect that it would make the most sense to correct the brewhouse batch rather than the final fermenter contents. It may take a little longer to get it right on the hot-side on each batch but seems like it would be a little more consistent.

This practice--adding water to a high gravity/ABV final product--is mostly used by the big guys so they can have exactly the same FG and ABV on each batch, thereby keeping the alphabet boys happy.

[kcolby]

This practice--adding water to a high gravity/ABV final product--is mostly used by the big guys so they can have exactly the same FG and ABV on each batch, thereby keeping the alphabet boys happy.

I had heard about this practice but figure the really big factory type of operations could afford all sorts of fancy equipment/processes that just don't make sense at the Micro/Craft scale.

[Rascals]

Definitely in the kettle to avoid possible contamination. Even adding at post boil prior to whirlpool would be fine.

What about adding cold sterile water to the kettle before transferring to the whirlpool?
We are thinking about doing this to get extra volume and the cool the wort slightly before adding the whirlpool hops, therefore getting more hop aroma.
Is there any issue adding cold water if there is DO in the water??

[istuntmanmike]

What about adding cold sterile water to the kettle before transferring to the whirlpool?
We are thinking about doing this to get extra volume and the cool the wort slightly before adding the whirlpool hops, therefore getting more hop aroma.
Is there any issue adding cold water if there is DO in the water??

I, too, am curious about this. I worry about hot side aeration but then again I wonder if I even should. I'm only making 3-15bbl batches, with some bottles and cans being packaged and almost all of it very hoppy...

[rdcpro]

I, too, am curious about this. I worry about hot side aeration but then again I wonder if I even should. I'm only making 3-15bbl batches, with some bottles and cans being packaged and almost all of it very hoppy...

I can't/won't comment on the whole HSA thing, but if you're concerned, I'd suggest de-aerating the water by boiling (or maybe use HLT water), and then run it through your chiller/HX to the kettle. Don't store it cold, unless you're using a closed and purged vessel.

The solubility of atmospheric oxygen at 185F (85C) is about 2.5 mg/l. So if that's low enough for comfort, then just run your HLT through the HX to the kettle. Otherwise, boil the water, then do the same thing.

Here's a chart of oxygen solubility vs. temperature

https://i.stack.imgur.com/OkTAi.png

Regards,
Mike Sharp

[JLL]

What about adding cold sterile water to the kettle before transferring to the whirlpool?
We are thinking about doing this to get extra volume and the cool the wort slightly before adding the whirlpool hops, therefore getting more hop aroma.
Is there any issue adding cold water if there is DO in the water??

Why are you worried about adding DO to the wort when you will be oxygenating very soon after during knockout?