Lallemand Windsor.

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jayk34

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What does it mean in the technical data for this yeast when it says medium attenuation ?

The reason I ask is that I pitched a packet into a 20.5 litre oatmeal stout batch. It started at an OG of 1.052 after about 9 hours and went like a rocket for just over 24 hours before stopping at 1.020 for the last 12 hours. No sign of bubbles in blow off now and temperature dropping constantly which would seem to indicate that the yeast is done. Will leave it another 12 hours before raising temperature but currently it's at 61% attenuation.

Is this the typical attenuation range for this ?

Edit: typos
 
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A easy way to understand it is each yeast is given a percentage of attenuation which means if a yeast is 75% attenuation it will generally ferment 75% of the fermentable sugars.
So higher gravity beers need a higher attenuating yeast to ferment lower down if that is what you want. To give you a rough example a wort of SG 1.040 will ferment down to 1.010 with a yeast of 75%.
Maybe your yeast has stopped at 1.020 because it did not have a high enough attenuation to ferment the sugars lower
 
Windsor will give anything BUT "medium" attenuation. Average is around 60%, which is in fact I think the lowest low attenuation of any commercially available yeast!

Manufacturers are not out to be truthful; they are out to sell yeast. So they'll say whatever they want to accomplish that goal.

It will complete its fermentation cycle in about 40 hours. It is a super fast yeast. I love it for session style ales where I want a lot of flavor but not a lot of alcohol. It's a tool in the toolbox.

See my summary on this yeast strain and everything else here:

https://docs.google.com/spreadsheets/d/16XRUloO3WXqH9Ixsf5vx2DIKDmrEQJ36tLRBmmya7Jo/edit?usp=sharing
 
Yeah, looks like it had stopped at 61% attenuation. Was wondering what the typical range for "medium" was. As I said will leave for another 12 hours before raising temperature and will leave it on fv for the full 2 weeks in the hope that it drops a couple more points.
 
I think it has virtually fully attenuated so you may struggle to get it lower but ypou never know so give it a try.
You need to check the attenuation in % which most yeast give you to make sure it will finish where you want it to but for some reason Windsor just says medium which is how long is a piece of string.
Windsor is usually used to give sweeter finish to a british style ale and that is why it has finished higher than you wanted as your OG is quite a bit higher than the normal English ale/bitters
 
I think it has virtually fully attenuated so you may struggle to get it lower but ypou never know so give it a try.
You need to check the attenuation in % which most yeast give you to make sure it will finish where you want it to but for some reason Windsor just says medium which is how long is a piece of string.
Windsor is usually used to give sweeter finish to a british style ale and that is why it has finished higher than you wanted as your OG is quite a bit higher than the normal English ale/bitters
It might not be a bad thing finishing at 1.020 or thereabouts for an oatmeal stout. I had originally intended to use yeast Irish Ale Yeast from a previous brew but instead chose Windsor due to the stated sweeter finish.
 
Yes it sounds as if it should be ok if its a stout wouldn't want a ale/bitter at that though as it would be too sweet for me but the stout will cut through some of the extra sweetness athumb..
 
I find it useful to make a note of the attenuation of each yeast for each brew, then you build up a record of what each one will typically achieve. They are pretty consistent if nothing goes wrong with your brew, so you can factor this in next time you brew as lower attenuating yeasts will need more grain to hit your target ABV.

Although it'll be weaker than you intended, it'll probably still be a very nice beer. I used their London ESB yeast recently and got 65%, most yeast I normally use are 75-80% and I didn't compensate in the recipe, so the brew was pretty weak. However, it was one of the best beers I've made.
 
I used it for a Porter last Christmas and it stopped at 1020. I was initially concerned it would leave a too sweet beer but it was actually delicious. The Windsor esters definitely added to the flavour too.
 
Thanks all for the info. Was the first time using this yeast and will remember for the next brew. I will be doing the milk Stout after this oatmeal had finished and was intending to use Windsor again. Not sure now ? Might consider empire ale m15 that I also have in stock.
 
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if you are happy with the Windsor taste wise etc just use it with a lower Gravity beer if not try The Empire or others .
I have used the Empire but can not find my notes so no real help there. athumb..
 
I believe Windsor doesn't ferment maltotriose(Lallemand London either?). That 75% attenuation may not take this into account?
 
I used it for an Irish Red a couple of months ago, attenuation came out at 69%, and brew finished a bit higher than expected at 1.015.
Giving it another go tomorrow in another Irish Red. If it doesn’t perform I’ll be switching to Wy1084 from now on.
 
Hi Alastair, try beior from cml, the ag kit i got from them used that yeast and the brew was very good
I haven't tried any CML yeasts yet. But now I've got enough fridge space for storage I'm going to get a few house strains gathered up. I'll have to have another look at their range.
 
What does it mean in the technical data for this yeast when it says medium attenuation ?

The reason I ask is that I pitched a packet into a 20.5 litre oatmeal stout batch. It started at an OG of 1.052 after about 9 hours and went like a rocket for just over 24 hours before stopping at 1.020 for the last 12 hours. No sign of bubbles in blow off now and temperature dropping constantly which would seem to indicate that the yeast is done. Will leave it another 12 hours before raising temperature but currently it's at 61% attenuation.

Is this the typical attenuation range for this ?

Edit: typos
You haven't posted your recipe but I'll take a guess from experience what's happened here...

I have a Porter I've fermented with MJ M36 and also W1318. I also have an American Stout fermented with BRY-97.

Despite what Brewer's Friend predicts, both finish in the region of 1.020 leaving me with very tasty and definitely not sweet beers in the region of 3.5-4.0% ABV, with a decent body that belies the modest strength.

My theory is that calculators - well, Brewer's Friend at least - massively over-predict the fermentability of all the dark malts used - brown malt, chocolate (rye) malt, roasted barley, dark & extra dark crystal malts...

(... It could also be the same with oats, don't know as I rarely use them)

In my case I have a very high proportion of these darker malts (30% of the grist or more) meaning the only real fermentables are the base malt.

Strangely, if I do a test calculation with just the base malt the predict final ABV is bang on - so I think the dark malts are mainly just adding to the OG but chuff all with regards to fermentables.

The exception to all this (because I really am nerdy enough to have plotted all this in Excel to analyse the trends!🤓📈📊) is my Baltic Porter - although it's a much stronger beer it has a much higher proportion of base malt to other stuff, so it has a lower FG.

Bottom line is, if the beer tastes good then drink it 👍 If you want a stronger beer then next time add more base malt but leave the other ingredients the same, or at least only add a little bit more - so if you add, say, 25% more base malt you might only add 5-10% more of the other stuff.

👍🍻 :beer1:
 
You haven't posted your recipe but I'll take a guess from experience what's happened here...

I have a Porter I've fermented with MJ M36 and also W1318. I also have an American Stout fermented with BRY-97.

Despite what Brewer's Friend predicts, both finish in the region of 1.020 leaving me with very tasty and definitely not sweet beers in the region of 3.5-4.0% ABV, with a decent body that belies the modest strength.

My theory is that calculators - well, Brewer's Friend at least - massively over-predict the fermentability of all the dark malts used - brown malt, chocolate (rye) malt, roasted barley, dark & extra dark crystal malts...

(... It could also be the same with oats, don't know as I rarely use them)

In my case I have a very high proportion of these darker malts (30% of the grist or more) meaning the only real fermentables are the base malt.

Strangely, if I do a test calculation with just the base malt the predict final ABV is bang on - so I think the dark malts are mainly just adding to the OG but chuff all with regards to fermentables.

The exception to all this (because I really am nerdy enough to have plotted all this in Excel to analyse the trends!🤓📈📊) is my Baltic Porter - although it's a much stronger beer it has a much higher proportion of base malt to other stuff, so it has a lower FG.

Bottom line is, if the beer tastes good then drink it 👍 If you want a stronger beer then next time add more base malt but leave the other ingredients the same, or at least only add a little bit more - so if you add, say, 25% more base malt you might only add 5-10% more of the other stuff.

👍🍻 :beer1:
The recipe was the oatmeal stout from the Greg Hughes book. Had the dry stout from the same book stop at 1.018 when using Nottingham and it was tasty. The second attempt at a slightly modified dry stout finished at 1.016 with Irish Ale Yeast. I think the reason why I'm getting slightly higher FG is because the batch is 23l bit I'm only getting 19-20 litres in the fv due to the massive boil off and hence the higher starting OG. I don't tend to liquor back all of the time so might explain the higher finishing gravity. Either way, they have all been very tasty stouts.

4.2 kg (83.5%) — Crisp Finest Maris Otter® Ale Malt — Grain — 6.5 EBC
250 g (5%) — whites oats — Grain — 3.9 EBC
200 g (4%) — Crisp Medium Crystal 240 — Grain — 265 EBC
160 g (3.2%) — Crisp Chocolate Malt — Grain — 1045 EBC
70 g (1.4%) — Crisp Roast Barley — Grain — 1375 EBC
Other (150 g)
150 g (3%) — Oat Hulls — Adjunct — 0 EBC
 
The recipe was the oatmeal stout from the Greg Hughes book. Had the dry stout from the same book stop at 1.018 when using Nottingham and it was tasty. The second attempt at a slightly modified dry stout finished at 1.016 with Irish Ale Yeast. I think the reason why I'm getting slightly higher FG is because the batch is 23l bit I'm only getting 19-20 litres in the fv due to the massive boil off and hence the higher starting OG. I don't tend to liquor back all of the time so might explain the higher finishing gravity. Either way, they have all been very tasty stouts.

4.2 kg (83.5%) — Crisp Finest Maris Otter® Ale Malt — Grain — 6.5 EBC
250 g (5%) — whites oats — Grain — 3.9 EBC
200 g (4%) — Crisp Medium Crystal 240 — Grain — 265 EBC
160 g (3.2%) — Crisp Chocolate Malt — Grain — 1045 EBC
70 g (1.4%) — Crisp Roast Barley — Grain — 1375 EBC
Other (150 g)
150 g (3%) — Oat Hulls — Adjunct — 0 EBC
What did you mash at? I've found that where I've mashed above the low 60s my attenuation has been lower than predicted for Windsor & London
 
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