How soon to add yeast

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Hopperty

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Murtons Porter Kit. It says wait until it cools to 18-21°c before adding yeast.

Problem is, the brew is at 26°c and ambient temp 21°c. So I doubt it will be down to 21 before tomorrow morning. What happens if the yeast is added arly ?
 
You now have to compromise. On one hand you want to get your wort down to as near as 21*C as you can before you pitch. But whilst your wort is sitting without yeast in it, it's at its most vulnerable in terms of getting infected, however small that risk might actually be.
I have pitched at 24* C before now, more out of ignorance than design and tbh nothing was spoiled.
So my suggestion is to put about 9-12" of cold water in a bath (not too much or your FV will float!) and dunk your FV in that, giving the bath water a swirl from time to time. You should get some cooling from that, although my mains water was running at 20*C last Friday, so the cooling potential is not to great. Or if you have a garden or builders trug fill that with cold water that you have chilled in the fridge if you have any spare 2 litre bottles kicking about. Also if you place a wet towel over the FV you will get an evaporative cooling effect from doing that.
And when you can achieve 23*C pitch the yeast but keep the chilling process going on until you hit 21*C or lower.
Finally when you do finally pitch the yeast give the wort a good thrash to re-oxygenate since the wort will have a greater capacity for oxygen absorption at the lower temperature
 
Seal it, give it some help to chill as per terrym's advice and wait. I'm forced to wait overnight every time I do a lager because it needs to get down to 10C.
 
Have you got any ice-packs in your freezer? Or small bags of ice cubes? (no need to open the bags)
 
I have stood it in a horse bucket full of water, but thats 15°.

it is down from 26 to 24.5. Am away out at 5 for rest of day,so wont be able to add yeast till morrow morning, so hopefully I can get it down to 22/23 by then, will that be cool enough ?

In hind sight (and maybe this is what I will do next time) after adding the 6 pints of boiling water to the kit I should have cooled that down to 55°C before adding the 34 pints cold - that would have given me the target of 21°C

What happens if it is too warm, does the yeast die ?
And what happens mid brew if there is a heat wave and the temp goes back up to 25 (unlikely I know) but would that kill the brew
 
it looks like it might make it

the blue line is the target time, if I miss that its tommor
xc1.jpg

you can see when it was stood in the horse bucket
 
I would if possible put some ice in the bucket water to cool it down further if you have some available but if you have to pitch higher and are worried of it rising through the fermentation ( the yeast once activated usually creates heat and will increase it by a couple or 3 degrees) use the bucket all the way through the fermentation to try and control the temp. If you can freeze a couple of pop bottles of water overnight you can use them to cool the bucket water down and proceed to do this through the complete fermentation its a good way of temp control in the warmer spells
 
@Hopperty
Personally I would pitch at whatever temperature you achieve at 5.00 pm this eve if you are going out, but leave the FV the horse bucket with some fresh cold water and then sort it out tomorrow on your return. The temperature rise in the first few hours after pitching is not very much at all, its only when the yeast really gets going and may not be until 24 hours on. Then do what @Baron says i.e. keep your beer in the horse bucket during fermentation to control the temperature using ice or chilled water as necessary.
As far as the initial hot water to the kit it's only necessary to add enough to get the LME mobile enough so that it mixes and also dissolve any LME you may have used. Dextrose or table sugar doesnt really need hot water just dilution. I have found the most you need is about 1.5 litres, but normally 1 litre off the boil water is enough
 
I've pitched even when it's still been in the 30s. By the time the yeast got going it was down to normal temperatures and took off like a rocket. No off flavour problems either.
Probably not best practice but I was off to bed and didn't want it sitting around for 8 hours un-yeasted.
 
I add less boiling water now to avoid this problem with kits. Just rinse the tins with hot tap water. Or don't let the kettle boil. Last brew I checked the temp as I topped it up. It was going to end up too warm so I added all the ice cubes from the freezer.
 
@Hopperty
Personally I would pitch at whatever temperature you achieve at 5.00 pm this eve if you are going out, but leave the FV the horse bucket with some fresh cold water and then sort it out tomorrow on your return. The temperature rise in the first few hours after pitching is not very much at all, its only when the yeast really gets going and may not be until 24 hours on. Then do what @Baron says i.e. keep your beer in the horse bucket during fermentation to control the temperature using ice or chilled water as necessary.
As far as the initial hot water to the kit it's only necessary to add enough to get the LME mobile enough so that it mixes and also dissolve any LME you may have used. Dextrose or table sugar doesnt really need hot water just dilution. I have found the most you need is about 1.5 litres, but normally 1 litre off the boil water is enough
Getting some good advice here Hopperty
 
Just to update - it was only down to 23.2 by the time I was going out so I chucked the yeast in and give it a good stir. Temperature immediately dropped to 20.4 (with just cooling the bottom third of the FV in the horse bucket I think all the cooled brew had just pooled at the bottom, stirring cooled the rest down)

All looks good this morning, top of the FV is all billowed up and the air lock pressured to one side, so I guess the fermentation is well under way. Temp dropped from 20.4 to 19.9 during the night.


Must make an effort on my next brew to calc the temperatures so after adding the water it starts off at 21°C. The whole process from taking the tops off the cans to adding the yeast at the correct temperature and getting the lid on should be taking less than 5 minutes (not 6 hours like yesterday)
 
I normally use a water bath for temperature control.
https://www.thehomebrewforum.co.uk/threads/how-to-set-up-a-water-bath-for-your-fv.66407/
Although cheap and cheerful, they work well enough below about 20*C. When ambient temperatures get to the lower 20*C range I still use the the bath and replace some water for chilled water from time to time. I don't brew in really hot weather, that's the preserve of saison yeasts and those with brew fridges.
 
I agree with teerym. Get the yeast in there. It's perfectly ok to pitch at a high temperature and then bring the wort down to a lower temperature. Bear in mind that the fermentation produces heat so you main struggle is going to be getting the temperature down and keeping it there AFTER pitching.
Sterilise some one litre PETS, fill with water and put them in fresh clean freezer bags then freeze them overnight. Drop one in the fermenting wort tomorrow morning. Pull it out when it's melted and put another one in until you're happy the temperature's under control. You need to do this for three or four days and then let the beer warm up for its diacetyl rest.
 
I pitch regularly around 22-23ºC and it's fine, could probably try even some degrees higher without much damage. But I ordered some kveiks, that will sort the temp problem.
 
Build yourself one of these bad boys: https://www.homebrewersassociation.org/pimp-my-system/son-of-a-fermentation-chiller/
I've had mine for over 10 years now and although a bit battered it works brilliantly. I built a temp controller from an STC1000 which I use to drive the cooling fan when it rises above target (generally 18.5) and a heat belt round the fermenter when it drops below (I used to just dangle a light bulb in there but upgraded to the heat belt lst year). It sits in my shed outside and maintains constant temperature in all conditions. When it was over 30c last year, I had to swap the frozen bottles out morning and evening, but that was a small price to pay for being able to brew all through summer (and winter). It can get down to about 12c with loads of ice bottles, changed frequently, but can't do largering.
 
I've pitched even when it's still been in the 30s. By the time the yeast got going it was down to normal temperatures and took off like a rocket. No off flavour problems either.
Probably not best practice but I was off to bed and didn't want it sitting around for 8 hours un-yeasted.

I have played it "fast and loose" on initial temps in the past, but only with US05 or Belgian sort of yeasts (Belle Saison or MJ's M31, that sort of thing) and pretty much noticed no difference in end result. It is once it starts the actual ferment at 20+ hours that you are in more difficult terrain, I feel.

Coopers recommend pitching their yeast (in kits) at 27C as max and this may be a useful benchmark, for a yeast that has evolved to cope with fairly high temps.
 
I have played it "fast and loose" on initial temps in the past, but only with US05 or Belgian sort of yeasts (Belle Saison or MJ's M31, that sort of thing) and pretty much noticed no difference in end result. It is once it starts the actual ferment at 20+ hours that you are in more difficult terrain, I feel.

Coopers recommend pitching their yeast (in kits) at 27C as max and this may be a useful benchmark, for a yeast that has evolved to cope with fairly high temps.
Its been between 21 and 22 (22.3°C max peak) since it started fermenting. I had not considered it generating its own heat (I am new to this)

My last brew (my very first ever) was between 17 and 20 throughout and it turned out just wonderful. The instructions say keep between 19 & 21 - will a degree too high make much diff ?
 
Don't do it with S-04. It's a complete baby and will go "My bwankettt has fawwen off my behhhhd!!" and then pretend to be dead until you smack it about with a bloody big stick. The general rule is pitch at or a few degrees under your temp and you can get away with fannying about unless it's that fekkin baby of a yeast.
 
Don't do it with S-04. It's a complete baby and will go "My bwankettt has fawwen off my behhhhd!!" and then pretend to be dead until you smack it about with a bloody big stick. The general rule is pitch at or a few degrees under your temp and you can get away with fannying about unless it's that fekkin baby of a yeast.
I need an interpreter :confused:
 
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