Topping up the kettle post boil

[contrarian]

I was having a conversation with the brewer at our local brewery who said that they top up their kettle prior to whirlpool. They brew over gravity and then top up to desired volume and SG.

It occurred to me that this seems even more applicable in a home brew environment where most people are limited to some degree by the size of their kettle but I have only heard a few stories of brewers topping up post boil and that was, from memory, brewers doing stove top BIAB at around 10L per batch.

As a basic example a post boil volume of 25L at 1.070 could make 39L of 1.045 wort which would be tricky in a pot that size with a full boil. There may be some modifications of hop schedule required but this should be fairly manageable.

The brewer I spoke to also said that it brought down the overall temperature of the wort for whirlpool and they had been happy with the results they had been getting from adding hops to the whirlpool rather than at flame out.

So are there any brewers out there that water down wort post boil? If not why not? If so how do you find the results?

 

[Gloveski]

If my OG is high I add water to dilute to get correct OG. Always filtered water and have never had any issues

 

[Sidney Harbour-Bridge]

Yep I do it quite a bit, I'm quite an enthusiastic boiler, always use Melbourne tap water.

 

[eldertaco]

Yeah I keep a cube of boiled and chilled water around for dilution post boil for if I'm doing a double batch in my crown urn. Seems to work well. Usually I add it to the fermentor but that's a good point next time I might top a portion into the urn first. It definitely helps bring temps down if you've got a cube that's been in the fridge that's for sure.

 

[EalingDrop]

I know some people put bags of ice in for a quick chill and dilution.

 

[contrarian]

Do you make any adjustments to hop additions when diluting or design the recipe based on the total finished volume?

 

[Gloveski]

For me it’s usually only a litre or 2 max ,I adjust whirlpool hops and dry hops to suit

 

[eldertaco]

I design the recipe based on finished volume. If you use beersmith you can set your recipe's top up water on the volumes area.

 

[contrarian]

I might give this a go over the weekend. was planning on brewing a saison anyway and too much is never enough so will aim to get 60L out of my 70L kettle with maybe a 15L top up post boil.

 

[dblunn]

Hi Mick,
The hop utilization goes down due the higher gravity in the boil but Beersmith et al will take care of that.
Dave

 

[user 35653]

I know some people put bags of ice in for a quick chill and dilution.

I remember reading a post from Kooinda brewery on here who did that on a warm summers day which resulted in an infection.

Here:
Plate Chiller in Kettle Without Tap?

I think people forget that just because water/ice is 'drinking quality' doesn't mean it's bug free, we've got stomach acid at a PH of 2 which kills most pathogens/bugs - your wort doesn't.

 

[contrarian]

Did a brew on the weekend where I managed 55L into cubes from a 70L kettle. It was an IPA at 1.060 with a 10L kettle top up post boil.

It was a very simple process to calculate although I think I underestimated the size of my cubes as I was filling 2 20L cubes and 1 15L cube and the last one was a few litres short. Next time I’ll aim for 60L.

I wouldn’t always want 3 cubes of the same beer but I’ll be doing this again when I want an extra one for a mate.