Imperial Stout Fermentation

[MashBag]

Used an aeration paddle to mkae sure that there was plenty of oxygen in there.
https://www.themaltmiller.co.uk/product ... on-paddle/

Just a thought, what is the width of the paddle please?

[Jocky]

They're the instructions.

https://www.themaltmiller.co.uk/product ... -nutrient/

Homebrew notes: Add by breaking open 1 capsule and pouring the supplement in 10 minutes prior to the end of the boil. OR, if your fermentation does not require a boil, open the capsule and pour in the supplement before you pitch the yeast.

Though the blister pack itself states "dosage recommendation: 1 capsule per 1.7 gallons (4.26 litres)".

The only time I use a tiny bit of Wilko's yeast nutrient is when I'm stepping up slants or making a starter from Proper Job dregs.

I’m pretty sure the packet says 1-7 gallons (4-26 litres), not 1.7 (4.26).

If anyone was wondering what servomyces is and why it’s expensive - it’s a zinc enriched dried yeast, so has to go through a whole growing and drying program to produce.

German brewers have to stick to reinheitsgebot, so they can’t add zinc directly to their brews. Instead they can use this because it’s technically yeast.

Daft. Although between this and acid malt I’m thinking of starting a program to cross hops with Irish Moss as I’d make a fortune from hops that are actually finings.

[f00b4r]

What yeast did you use to ferment with and how much of it?

I do smaller batches than most - I have a 15l all in one.

I should have made a note of how much it yielded - I think it was around 12l into the fermentor.

I used 2 packets of dry yeast Safale S-04.

Used an aeration paddle to mkae sure that there was plenty of oxygen in there.
https://www.themaltmiller.co.uk/product ... on-paddle/

Have I read that right? 2 packs In 12 lites?

Once you get to those kind of alcohol levels you want to be going to at least those levels. It’s probably much better to brew a small beer first though and use the yeast cake.

[MashBag]

Really? I suspect you full of Christmas cheer

[Northern Brewer]

This is a useful presentation about big fermentations :
https://quaff.org/wp-content/uploads/20 ... tion-1.ppt

[MashBag]

Good ppt.

Certainly confirms my experience and my concern.

[f00b4r]

Good ppt.

Certainly confirms my experience and my concern.

In what way?

[MashBag]

Page 5
"resist the urge to over pitch"

23g in 12l IMO is an overpitch.

[f00b4r]

Page 5
"resist the urge to over pitch"

23g in 12l IMO is an overpitch.

Hmm I would disagree That PPT appears to be aimed at commercial breweries? Although it has interesting info in it, commercial brewery pitch rates are often much higher than that used by homebrewers so you are comparing apples and oranges. An over pitch by a commercial brewery is often very different to that by a homebrewer.

For example, Gordon Strong (in Brewing Better Beer) suggests 2 packets of yeast for a 1.050 beer standard be length with an extra pack for every 25 gravity points. That is a similar rate to what was posted earlier for the 12L beer.
The other issue with very high alcohol beers is that if fermentation stalls at a high alcohol level there is a good chance you will never get it going again with fresh yeast, due to the very hostile environment (been there before myself and even Brett couldn’t shift it), hence why a lot of people make a small beer first and pitch on some of the cake (or sometime all depending on the initial batch size/strength). A slight over pitch at homebrewer level on a heavily malt driven beer may make little difference to the taste anyway, unlike with a session bitter.

[MashBag]

I agree there is little chance of a flavour issue, just seems a lot, but I am basing that on session ales, many many hectolitres of red wine and also some big washes. Never a big stout so I am happy to take your word for it.... Well TBH you and Gordon

Thanks. I have learnt something there.