First AG brew day - the missing litre.

[JohnB]

Hi folks,
Yesterday was my first go at an all grain brew. I followed the simple recipe I found on here for a SMaSH brew, but doubled the recipe for 10L. Everything went fine until I got right to the end and wondered if anyone can shed a bit of light on this and suggest my next step. I'll explain in my very simple terms.
I started with 12L water for a 10L batch. This gave me 5L for the mash and 2 x 3.5L for the batch sparge process.
1. Mash went fine (need to get a grain bin for larger batches).
2. Batch sparged and this too went spot on - ended up with 11L (11.2L) of wort, as calculated.
3. Into the boiler, and first hops (I split the hops equally into 60 minute and 15 minute additions).
4. At the end of the boil I was 1 L down on my calculations and only had 9L of wort. I maintained a really good rolling boil which evaporated more than I had anticipated, i.e. 2L went AWOL!

Pre-pitch OG ended up at 1052 rather than the 1045 (at 20 DegC) that I had calculated.

I cooled everything down at 9L , and pitched the yeast at 20 DegC. This morning it is bubbling away merrily.

The question now is should I, or could I, have added cold water to get to my 10L, I appreciate the final ABV will be much higher than I had anticipated, depending on attenuation. But I wanted a lower ABV to make a lighter finished product.

The plan is to adjust this for the next brew and add an extra litre to the starting volume, however, I wondered about adding water before fermenting and if cleaned (iced bottled water, or iced sodium met' treated tap water) could be used during the chilling process and to increase the volume back to the calculated by replacing a small part, say 10% of the batch with iced water?

I have read on another forum that this is not a good idea, but with little explanation apart from introducing nasties into the wort from cold water.

Many thanks in advance for a bit of help on this one. And I'm hoping it may help other beginners to get a bit closer to their target than I did.

Regards,
JB.

 

[Dutto]

I always finish short of the 23 litres I want in the FV so I always top up with cold water prior to taking the OG.

The loss comes from wort still left within the hops and hop bags, evaporation and the amount of debris I leave behind in the Boiler. It varies from brew to brew.

The reason tap water isn't recommended for brewing is that it can contain chlorine and minerals that affect the taste of the brew so I have one of these fitted to the water supply to the tap ...

https://www.amazon.co.uk/dp/B005CAZDBY/?tag=skimlinks_replacement-20

They're not cheap but they are effective and (for me) a better alternative than treating the water or using bottled water.

BTW if there are so many "nasties" in the water that comes out of the taps in your home, you should be more worried about poisoning your nearest and dearest than worrying about introducing something into your brew!

 

[MyQul]

I cant help you with where your missing 1L went but I regularly add water as I'm cant be bothered with being accurate with my calculations. If it's a dark beer I just put it in straight from the tap as my water isnt chlorinated enough to cause chloraphenols in the beer. If it's a light beer I acidify it like the rest of the water for the beer. I dont try to santitise it or anything

 

[Gerryjo]

As it was your first brew on AG I'm assuming that you haven't calibrated your equipment i.e tested your boiler/pot for boil off rate and bear in mind that this will differ due to the size and dimensions of your pots surface area.
Your efiency is actually quite good as @1.045 you would have had 10.40 litres of wort.

Test your equipment by boiling 10l of water using the same pot and measure after an hour of boiling and this should give you a ballpark figure to work from.

 

[Drunkula]

You can add the water when it goes into your fermenter and even add it at bottling time. I regularly use demijohns to brew and you get too much krausen in them so I'll put 3.5 to 4 litres in then make it up to 4.5 litres at bottling. You can boil and cool the water and campden tablet it if you want.

 

[chthon]

Using the equation V1 x (OG1-1) = V2 x (OG2 - 1), and then calculating (OG2 - 1), you would have had a FG of 1.046 if you had added that 1 liter post-boil.

See http://beerandwinejournal.com/cv-equation/

 

[JohnB]

I was thinking of have some reserve water available, just a couple of litres, so if I was a bit short I just just bring 'er up to volume.

@chthon thanks for that, you saved me some research, 'cos my next thought was hunting down the physics behind adding water to a solution of water and sugar!

It seems I am a bit too serious and worried by stories of contaminants. Sanitary but not sterile seems to be the order of the day. And the next plan is to check just how much water I can boil off in 60 minutes because that is where my calcs went off piste. Thanks for all your thoughts folks.

BTW Dutto - now there's an idea

 

[Slid]

Very simplistically, when I remember doing half batches in a pot and a bag with a double sparge, I would lose nearer 3L than 2L. So next time try using another litre for sparging and see what happens.

You can boil the resulting wort in one main pot and a spare litre from the second sparge in a second pan, without any hops, until it all fits into the main pot.

 

[MyQul]

@chthon thanks for that, you saved me some research, 'cos my next thought was hunting down the physics behind adding water to a solution of water and sugar!

Im **** at maths so I just use this dilution calc

https://www.brewersfriend.com/dilution-and-boiloff-gravity-calculator/

 

[Zephyr259]

The 1L assumed boil off was probably just off, i get about 3 l/hr, but all systems will vary. My first batch did the same and way overshot the gravity due to under volume, just as well as otherwise the demijohn would have overflowed. Enjoy the beer and welcome to AG brewing.

 

[Brewed_Force]

You could try adjusting your hops and do a 30 minute boil to reduce evaporation.

 

[ACBEV]

For a first AG brew, I think it went swimmingly... When I started I would be happy to get beer and didn't worry much else.

If I'm short, I add extra water to my batch priming solution at bottling time. Doesn't happen often nowadays as I know exactly how much brew water I need at the start.

 

[JohnB]

Hi all, sorry I have not bee about to read all the replies, but finally got round to it (or a round tuit!) tonight. Perils of long-haul truck driving I guess.

Well, after posting this thread I know now where the missing litre went. My boil-off rate is close to 3.2 litres per hour, where I had calculated about 1 litre. So for my next brew I added this amount to the initial calculation and ended up with 10.5 litres of wort for a calculated 10 litre brew. So that bit is more or less sorted.

Now it is down to the final stages of carbonation, and conditioning, then give it a try to see what I have made. The initial sample - cos I cleared in a secondary and sampled at bottling time - seems to be spot on what I had aimed for, a brown ale with about 5% ABV and a bit of a bite to it. It tastes good - and the next problem? Hooked on AG brewing, is there a clinic somewhere for those afflicted? Seriously, this tastes way beyond anything that comes out of a kit. I'm impressed and would like to thank everyone for their help - including all those that might read/respond to the open FV thread.

Thanks all.