Consistent problem with FIRST batch - Lager Yeast

[Goose]

This problem really buggering me and appreciate some input.

I've been making 5 litre starters from 2 x Wyeast smack packs (using 2042 Danish). I do this by adding 500g of DME with a 1/2 tsp of wyeast nutrient to a bit more than 5 litres of water and boiling for 10 minutes or so, cooling, then pitching the smackpack contents. I then let it do its thing on a stirplate for 5 days or so till I have a healthy crop. The starter is held at 21 deg C. the day before brewday I cool to pitching temperature (12 deg C) and allow yeast crop to settle.

For this first batch the fermentation always takes off very quickly and is done within 10 days, at around 1.020 I raise slowly to 19 deg C for 2 days for a diacetyl rest, then crash cool to 4 deg c for a day before kegging.

I pump out what I can of yeast slurry and use what is left for the next brew...

My issue is the first batch is just shit by lager standards. Cant put my finger on it to describe flavour. The only thing I could associate it is a hint of dank caramel. A sweetish aroma. Not a diacetyl taste but some might say similar. I have no patience nor storage to see if this will lager out, so it becomes fertiliser.

The next batches, seem to improve magically, and ferment out within 5 days. Clean, and no diacetyl rest required. I have done this for 6 batches and would go further except I have no more space to keg.

I can only figure this is due to an improved vitality and cell count on subsequent batches. But in essence it seems I am simply doing a step up using 45 litres of wort for the first batch and ditching the "spent" beer. This cannot be right.

I have used Mr Malty calculator. According to this I need 400 billion active yeast cells for a 45 litre lager. The calculator says I need 3 "vials or packs" of 2 month old yeast and a 1.88 litre starter if I use a stirplate. Firstly, I've never heard of anyone pitching 3 wyeast activator packs into a 2 litre starter. Second, each of the wyeast activator packs is supposed to contain 100 billion cells, I assume if used on day of manufacture which of course I can't. So I use 2 packs and do a 5 litre starter straight.

Would I be better off using just one smackpack in 500 mls and using the 10 x rule then step up to 5 litres ?

I'd appreciate any advice or thoughts as to what is going on here.


:blink:

 

[Black n Tan]

I then let it do its thing on a stirplate for 5 days or so till I have a healthy crop. The starter is held at 21 deg C. the day before brewday I cool to pitching temperature (12 deg C) and allow yeast crop to settle.

Would you explain this process in a little more detail? Do you pitch the whole starter or just the yeast? 5 days is too long and probably adversely affects yeast health. I let mine go 2 days before crash at 0C overnight and then throw away the spent wort and pitch just the yeast.

Would I be better off using just one smackpack in 500 mls and using the 10 x rule then step up to 5 litres ?

I'd appreciate any advice or thoughts as to what is going on here.


:blink:

You can set the criteria in the MrMalty yeast calculator to use fewer yeast packs (and a bigger starter). If you can step your starter you can save yourself some dollar, although I don't think that is the reason for your poor first batch. For lagers I always step my starter, 1 pack into a typically 1L starter then 4L (for a 42L batch).

 

[Camo6]

Hey Goose,

I'm a bit blase with my yeast starters nowadays and rarely use software to calculate as I tend to use the same technique repeatedly. But a quick check on both Mr Malty's and Brewer's Friend yeast calculators indicate for a 45l batch of lager at 1048 OG you'd need 800 billion cells. Sounds like you're under pitching.

Maybe try the brewer's friend claculator which allows for stepping starters and see what this recommends. The few lagers I have done have called for at least 5l starters for a single batch and I've still detected a 'caramel' taste in one of them I put down to diacetyl.

If he doesn't chime in maybe PM Labels who, IIRC, has focused on perfecting brewing good lagers.

 

[Black n Tan]

Didn't realise you batch was 42L, but Cam06 is spot on with the under pitch comment. May be you have MyMalty set to ale not lager? I suspect your 5 days on the starter is not doing you any favours either.

 

[Goose]

Would you explain this process in a little more detail? Do you pitch the whole starter or just the yeast? 5 days is too long and probably adversely affects yeast health. I let mine go 2 days before crash at 0C overnight and then throw away the spent wort and pitch just the yeast.


You can set the criteria in the MrMalty yeast calculator to use fewer yeast packs (and a bigger starter). If you can step your starter you can save yourself some dollar, although I don't think that is the reason for your poor first batch. For lagers I always step my starter, 1 pack into a typically 1L starter then 4L (for a 42L batch).

hey lads.

Pitch just the yeast after decanting the spent liquor above, I taste and smell the stuff, last few have been ok. I find it takes a couple of days for the wort to turn milky indicating growth... as soon as I see this I cool it down, 4-5 days has been the total time...

I'm a bit blase with my yeast starters nowadays and rarely use software to calculate as I tend to use the same technique repeatedly. But a quick check on both Mr Malty's and Brewer's Friend yeast calculators indicate for a 45l batch of lager at 1048 OG you'd need 800 billion cells. Sounds like you're under pitching.

Ok, re-ran the calculator. Yes you guys are correct. My bad (with thanks.. :blink: ), It does calculate 800 billion, BUT in such case tells me 3 packets and still less than a 5 litre starter required....(4.39 litres).

so I should still be ok on cell count ?

thanks for the brewers friend calculator. It also reckons 5 litre starter should to the trick and also comes up with 800 billion.

 

[JasonP]

This problem really buggering me and appreciate some input.

I've been making 5 litre starters from 2 x Wyeast smack packs (using 2042 Danish). I do this by adding 500g of DME with a 1/2 tsp of wyeast nutrient to a bit more than 5 litres of water and boiling for 10 minutes or so, cooling, then pitching the smackpack contents. I then let it do its thing on a stirplate for 5 days or so till I have a healthy crop. The starter is held at 21 deg C. the day before brewday I cool to pitching temperature (12 deg C) and allow yeast crop to settle.

For this first batch the fermentation always takes off very quickly and is done within 10 days, at around 1.020 I raise slowly to 19 deg C for 2 days for a diacetyl rest, then crash cool to 4 deg c for a day before kegging.

I pump out what I can of yeast slurry and use what is left for the next brew...

My issue is the first batch is just shit by lager standards. Cant put my finger on it to describe flavour. The only thing I could associate it is a hint of dank caramel. A sweetish aroma. Not a diacetyl taste but some might say similar. I have no patience nor storage to see if this will lager out, so it becomes fertiliser.

The next batches, seem to improve magically, and ferment out within 5 days. Clean, and no diacetyl rest required. I have done this for 6 batches and would go further except I have no more space to keg.

I can only figure this is due to an improved vitality and cell count on subsequent batches. But in essence it seems I am simply doing a step up using 45 litres of wort for the first batch and ditching the "spent" beer. This cannot be right.

I have used Mr Malty calculator. According to this I need 400 billion active yeast cells for a 45 litre lager. The calculator says I need 3 "vials or packs" of 2 month old yeast and a 1.88 litre starter if I use a stirplate. Firstly, I've never heard of anyone pitching 3 wyeast activator packs into a 2 litre starter. Second, each of the wyeast activator packs is supposed to contain 100 billion cells, I assume if used on day of manufacture which of course I can't. So I use 2 packs and do a 5 litre starter straight.

Would I be better off using just one smackpack in 500 mls and using the 10 x rule then step up to 5 litres ?

I'd appreciate any advice or thoughts as to what is going on here.


:blink:

What's your recipe? A dare say that your first batch has stalled due to under pitching or lack of oxygenating. 1020 sounds high unless it's a dopple bock or something. What fg are the subsequent beers finishing at?

 

[Black n Tan]

Ok, re-ran the calculator. Yes you guys are correct. My bad (with thanks.. :blink: ), It does calculate 800 billion, BUT in such case tells me 3 packets and still less than a 5 litre starter required....(4.39 litres).

so I should still be ok on cell count ?

thanks for the brewers friend calculator. It also reckons 5 litre starter should to the trick and also comes up with 800 billion.

I can't recreate this on MrMalty. For a 2 month old pack and a 42L [email protected] I get 3 packs required in a 9.3L starter. 2 packets and a 5L starter is still likely to be an under-pitch for this size batch. Wyeast has a yeast calculator that allows for step starters.

 

[Camo6]

Agree with Black N Tan.

Goose, have you tried moving the slide bar to the right to indicate using only 2 packs?

 

[Camo6]

What's your recipe? A dare say that your first batch has stalled due to under pitching or lack of oxygenating. 1020 sounds high unless it's a dopple bock or something. What fg are the subsequent beers finishing at?

Sounds like 1020 is when the OP is starting his diacetyl rest. I don't think there's any mention of FG's.

 

[Lemon]

Honestly this discussion is making my head spin. What I do know it is practically impossible to over pitch a lager in a homebrew sense.
So what I do is make a sacrificial lager, pitch two packets of wyeast, I have pitched 6 packets of dry to prove a point but, then pitch the next brews onto the cake to ensure adequate pitch rate.
The first brew is good, the following, great. Even better with lagering.
Lemon

 

[JasonP]

Sounds like 1020 is when the OP is starting his diacetyl rest. I don't think there's any mention of FG's.

I took it was fg was 1020. A diacetyl rest should be done after fermentation complete. Either way recipe and details would be useful.

 

[Goose]

I can't recreate this on MrMalty. For a 2 month old pack and a 42L [email protected] I get 3 packs required in a 9.3L starter. 2 packets and a 5L starter is still likely to be an under-pitch for this size batch. Wyeast has a yeast calculator that allows for step starters.

thanks, what am I doing wrong ? below this time fiddled the production date to 2 mths but didn't fiddle the growth bar at the bottom.

 

[Camo6]

I took it was fg was 1020. A diacetyl rest should be done after fermentation complete. Either way recipe and details would be useful.

From my readings a diacetyl rest should be started a few points off final gravity. A quick search finds it mentioned here.

But I can never warrant the time and effort to do lagers although I usually raise my ales to 20c if and when I remember.

 

[Goose]

Either way recipe and details would be useful.

sure:

Mash
1hr 64 deg C, mashout 75 deg C

Ingredients

7.50 kg Pilsner (2 Row) Ger (3.9 EBC) Grain 1 88.0 %
1.00 kg Munich Malt (17.7 EBC) Grain 2 11.7 %
0.02 kg Acidulated Malt (3.5 EBC) Grain 3 0.2 %

Boil volume 54 litres:
75.00 g Hallertauer Tradition [4.40 %] - Boil 60.0 min Hop 4 19.7 IBUs
50.00 g Hallertauer Tradition [4.40 %] - Boil 30.0 min Hop 5 10.1 IBUs
20.00 g Hallertauer Hersbrucker [1.60 %] - Boil 15.0 min Hop 6 0.9 IBUs

15 mins before flameout, 1 tsp kopperfloc, 1 tsp wyeast yeast nutrient

crash chilled 2 stage plate chiller, oxygenated in line with injected O2.

Yeast
2.0 pkg Danish Lager (Wyeast Labs #2042) 2 packs, 5 litre starter

 

[indica86]

. A diacetyl rest should be done after fermentation complete.

Nope. The idea - from what I have read - is for the yeast to chew through the shit they have left behind, and they need fuel to do this.

 

[Black n Tan]

thanks, what am I doing wrong ? below this time fiddled the production date to 2 mths but didn't fiddle the growth bar at the bottom.

That is telling you to use 5 packets and 5L starter. You used 2 packets so your final number will fall well short. Drag that growth factor scroller all the way to the right. But for stepped starters Wyeast will be easier for you. For a fairly fresh pack of yeast, say within 2 months, then a 1L then 4L step starter will get you close of 800billion.

 

[Goose]

appreciate the input.

next time will be a single packet into 1 litre, step up to 4 (or 5?).

will revert with results and bump this thread by which time it'll likely be resurrected from page 10

 

[SnakeDoctor]

Personally i'd do a 1 litre and then 5 litre from a single pack, it will do it on the stir plate.

Two packs of fresh yeast into 5 litre starter on a stir plate should have got you up near 800 bill cells but it's very close to or is a massive underpitch for a starter if they aren't fresh.

 

[Goose]

Personally i'd do a 1 litre and then 5 litre from a single pack, it will do it on the stir plate.

Two packs of fresh yeast into 5 litre starter on a stir plate should have got you up near 800 bill cells but it's very close to or is a massive underpitch for a starter if they aren't fresh.

I figured that growth may take me up to the magic number even if I had only a few viable cells to start with.... where I am falling down is that at some point growth stops (why ?) and I just get respiration leaving me with an insufficient cell count.

I need to understand more about what causes / stimulates growth, and then what causes it to stop replicating and then just get into respiration mode... sources welcome...

 

[Camo6]

'Yeast' by Chris White is a great resource.