Yeast not working

[jerseyboyd]

Hello,
I am on my 2nd batch of full-mash home brew, and for the 2nd time I seem to be having yeast problems.
For my 1st attempt I used Safale 04, made up a yeast starter and all seemed well but I think it succombed to temperature shock, as I left the beer overnight in an unheated area and the outside temperature was around 4 degrees C.
For my 2nd attempt this weekend I used Danstar Windsor yeast. Everything seemed fine a few hours after pitching, a head had started to form, but 24 hours later activity seemed to have ground to a halt. I roused and aerated but to little effect, as there appears to be little sign of activity this morning (if any, just a slight puff of gas when I unscrewed the cap) and above all absolutely no head or foam.
What am I doing wrong?

 

[ManseMasher]

Hello,
I am on my 2nd batch of full-mash home brew, and for the 2nd time I seem to be having yeast problems.
For my 1st attempt I used Safale 04, made up a yeast starter and all seemed well but I think it succombed to temperature shock, as I left the beer overnight in an unheated area and the outside temperature was around 4 degrees C.
For my 2nd attempt this weekend I used Danstar Windsor yeast. Everything seemed fine a few hours after pitching, a head had started to form, but 24 hours later activity seemed to have ground to a halt. I roused (if any, just a slight puff of gas when I unscrewed the cap) sign of activity and above all absolutely no head or foam.
What am I doing wrong?

Dry yeast works well if you rehydrate it. The temperature range is very important, and differs from yeast to yeast. Your first one will definitely have not liked 4°c, but if it had warmed up to the correct range, may very well have started again. Did you rehydrate the Windsor? What temperature did you pitch at and what is it sitting at now?

 

[jerseyboyd]

I made up a yeast starter with the Danstar Windsor, following the instructions in Graham Wheeler's CAMRA book Brew Your Own British Ale.
I pitched at 25°C.
It was 14°C outside when I brought the beer back home in the boot of my car from my mate's place where we brew.
It is now sitting in a room where the temperature is about 20°C.
I'm also wondering if our mash was inefficient (again referring to Graham's book). We didn't obtain a thick, porridge like mass, pretty liquid really. Nice colour, but maybe not enough of what the yeast needs to work?

 

[ManseMasher]

Dry yeasts only need rehydrating really, no need to make a starter. IIRC Windsor's range is between 17 -21°c. I think temperature may well be your issue. There are also various mashing/sparging calculators available. Have a look in the calculators section at the top of the page. There are others also readily available.

 

[jerseyboyd]

OK, thanks for your help.
By the way, my Danstar Windsor supplier is Lallemand. Don't know if this is an issue or not.

 

[Fore]

Liquid yeast doesn't come with a lot of active cells, so a starter is needed to build them up. Dried yeast however, as per your Windsor, comes with a lot of potential active cells, so you only need to rehydrate. Dry yeast doesn't like sugar solution in which to rehydrate, so if you were to drop the dry yeast straight in the fermenter (as many people do), you loose some 40% of potential cells. By rehydrating in water before hand, you loose only a fraction of that. To rehydrate, cool 10 times the yeast weight of pre-boiled water to about 30 degrees, and add the yeast (all sterile and loosely covered of course). 15 minutes in, stir. Pour it in your fermenter 5 minutes later. Don't pour in unless within 5 degrees of the wort; I normally speed up cooling by sitting in a cold bath.

For yeast storage, freezing the yeast packet significantly prolongs the best before. Just be sure to leave ample time to warm to room temp before using. If you follow all this, then you can put the question of yeast viability behind you. Blankets, lots of blankets, and a hot car!

 

[jerseyboyd]

OK, thanks for all that advice!

 

[ManseMasher]

OK, thanks for your help.
By the way, my Danstar Windsor supplier is Lallemand. Don't know if this is an issue or not.

Lallemand are the 'manufacturers' of Danstar yeast, or the producers/growers whatever yeast makers are called!

 

[duncans]

Fermentation was active but over quickly - means your yeast did something. What was your hydrometer reading before and after?

 

[MyQul]

You are aware that you'll only get a medium (about 60%AA-70%AA) attenution with windsor? That might be why it was over so quick as the yeast has done as much work as it's going to and has now knocked off and gone down the pub.

 

[jerseyboyd]

To answer Duncans and MyQul:
The only hydrometer reading we took was post-boil after cooling, from the fermenter: 1025.
Guys from another forum have confirmed this is very low! I have the feeling we are not doing the mash right, what you're saying seems to confirm that.
What do you mean by attenuation? Sorry,, too technical for me at this stage in my apprenticeship!
But I like the idea that the yeast has knocked off and gone down the pub :lol:
There's a brewpub near where I live that's started doing home-brewing workshops, I think I'm going to sign up for an all-grain session so I can see for myself what a proper mash should look like.
Thanks again for your help.

 

[ManseMasher]

That is indeed low for a brew before it has started fermenting. So you are right to start thinking about your processes before this stage. As a rough ballpark figure, for every 1kg grain, you are looking to need 2.5l water for the mash, so a recipe with a total grain bill of 5kg will require around 12.5l of water. The temperature range for mashing is quite small, specific and needs to be kept constant for a required length of time (again ball park - depending on the style of beer you are after), but I aim to mash at 65°c for 60 minutes.

 

[jerseyboyd]

I'm a bit confused by those figures.
I'm following the London Pride recipe in Graham Wheeler's CAMRA book, which is 4kg of pale malt and 400 g of Crystal malt for 25 litres, that's double what you're saying!

 

[ManseMasher]

I'm a bit confused by those figures.
I'm following the London Pride recipe in Graham Wheeler's CAMRA book, which is 4kg of pale malt and 400 g of Crystal malt for 25 litres, that's double what you're saying!

The 25 litres will be what you are aiming to get into the fermentor. You mash with much less, then sparge the mashed grain to wash all the fermentables out. It is the sparging that gives you your final quantity. If you mashed, which it sounds like you may have done, with the 25 l from the book, there is your issue right there I would say....

 

[MyQul]

Attentuation is how much percentage of the sugars in the wort have turned to alcohol. In the reciepe your following if you hit the target Original Gavity measurment of 1.040 and hit the target Final Gravity measurement of 1.010, it will give you 75% attenuation. But like I say windsor gives about 60%-70% attenuation which will probably give you a FG of 1.016-1.012. But this will also depend on mash temp too.

 

[jerseyboyd]

Aha! I have just spotted the line in the recipe that says: mash liquor 11.1 litres. Duh!
Oh well, I guess we can put that down to inexperience, or put simply, "Learning the hard way".
No wonder our mash is pretty liquid! And no wonder sparging was pretty ineffectual.
At least I've eliminated yeast and temperature as potential problems.

 

[Covrich]

To answer Duncans and MyQul:
The only hydrometer reading we took was post-boil after cooling, from the fermenter: 1025.
Guys from another forum have confirmed this is very low! I have the feeling we are not doing the mash right, what you're saying seems to confirm that.
What do you mean by attenuation? Sorry,, too technical for me at this stage in my apprenticeship!
But I like the idea that the yeast has knocked off and gone down the pub :lol:
There's a brewpub near where I live that's started doing home-brewing workshops, I think I'm going to sign up for an all-grain session so I can see for myself what a proper mash should look like.
Thanks again for your help.

Yeah to be honest it sounds like something needs looking at with your mashing and sparging

1025 starting gravity is not right and you will probably end up with about 2% beer..

You could add some malt extract maybe to boost it back up perhaps.

 

[jerseyboyd]

Thanks for that suggestion, I added 500 g of malt extract last night and it got the yeast working again.
Things seem to have slowed this morning, but at the start a nice head had formed. I was beginning to wonder if I would ever see that!
Hopefully I've boosted it a bit like you say. Do you think it's worth putting more extract in or maybe some sugar to get a bit more alcohol?

 

[jerseyboyd]

A quick hello to all those who chipped in their nuggets of wisdom to help me through my first attempts at full mash brewing.
As I'm doing all this with a group of friends, I'm not brewing as regularly as most of you guys out there, as it's not always easy for us to get everyone together on the same weekend, but the next attempt is scheduled for 30 April.
We actually tasted the 'small beer' that resulted from my massive miscalculation of the quantity of mash liquor required.
The taste was obviously more akin to tea than beer, but I'm really happy to report that our beer cleared unaided without finings and it also had good natural condition. So we must have got something right, I guess. I'm really encouraged and can't wait until the next batch, this time with the right quantities!