Wyeast 1968 - London ESB: finishes high?

[darlacat]

I recently made a porter using Wyeast 1968. OG 1.050, mashed at 67, but it finished at 1.020. Brand new package, so not long since manufacturing date. I raised the temperature for a few days up to 20 to see if it would get down a few more gravity points, but nothing.

This is my first time using 1968 - anyone else experience anything similar?

I had also intended to repitch the yeast from this beer (harvested at the weekend) into a dark mild I'm brewing this Friday. Given the high finishing, should I bother? Or perhaps pitch it alongisde some Nottingham for greater attenuation? Quite a small and compact yeast cake from this beer too - collected 1 litre, which, once settled, has amounted in c.400ml of yeast slurry. Contrast this to my last brew with Wyeast 1469*, which ended up with a load of yeast slurry (and high attenuation).

*1469 worth pitching into a dark mild? I harvested also...

 

[MickDundee]

The WYeast website says “Attenuation levels are typically less than most other yeast strains which results in a slightly sweeter finish”, and states an attenuation of 67-71%(London ESB Ale | Wyeast Laboratories)

Your 1.050-1.020 is 59% attenuation, which is 4 points higher than if it had hit the 67% - did you use a yeast starter? If not it might account for the slightly lower than quoted attenuation.

 

[darlacat]

The WYeast website says “Attenuation levels are typically less than most other yeast strains which results in a slightly sweeter finish”, and states an attenuation of 67-71%(London ESB Ale | Wyeast Laboratories)

Your 1.050-1.020 is 59% attenuation, which is 4 points higher than if it had hit the 67% - did you use a yeast starter? If not it might account for the slightly lower than quoted attenuation.

I didn't use a starter - I've not had any problems pitching from the activator pack in the past, and the pack was brand new. The 1469 I mentioned was also a new package into similar gravity wort, and had high attenuation.

 

[Ben034]

Starter is a good idea usually, as you don't know how the yeast has been stored and shipped from the states. The 1469 may have had sufficient cells where as the London ESB may not have when pitched. A starter will help with consistency. What was your mash temp?

 

[darlacat]

Starter is a good idea usually, as you don't know how the yeast has been stored and shipped from the states. The 1469 may have had sufficient cells where as the London ESB may not have when pitched. A starter will help with consistency. What was your mash temp?

Mashed at 67, as I wanted a but of residual sweetness/body. In hindsight, perhaps I should've opted for 64.

Might make starters in the future, to be on the safe side. As I said, haven't had an issue with Wyeast packs being pitched directly in the past into average gravity wort. Smack pack swelled fully after breaking the nutrient pack.

Any thoughts on my question re repitching this yeast into a dark mild?

 

[MrRook]

1968 can be made to ferment more by rousing it back into suspension.

 

[Ben034]

I would pitch it personally. You've basically made a starter now and can pitch a good amount of yeast. For the style of beer you're making, a good bit of residual sweetness will work well.

 

[darlacat]

1968 can be made to ferment more by rousing it back into suspension.

I tried this - roused and raised the temperature up to 20c: nothing. Done at 1.020.

 

[darlacat]

I would pitch it personally. You've basically made a starter now and can pitch a good amount of yeast. For the style of beer you're making, a good bit of residual sweetness will work well.

Around 400ml ok to pitch? Maybe 350ml discarding the bottom layer?

I'm aiming to make 1.038 wort, mash at 67c. I was half tempted to pitch a packet of dry yeast alognside it - maybe Nottingham or S04 - just to guarantee better attenuation while retaining the flavour of 1968. Good/bad idea?

Here's my recipe for the mild:

Original Gravity (OG): 1.038 (°P): 9.5
Final Gravity (FG): 1.010 (°P): 2.6
Alcohol (ABV): 3.73 %
Colour (SRM): 24.1 (EBC): 47.5
Bitterness (IBU): 19.7 (Average)

77.12% Maris Otter Malt
5.14% Biscuit
5.14% Crystal EBC 135
5.14% Torrified Wheat
3.86% Carafa III malt
3.6% Chocolate

0.7 g/L Challenger (6.1% Alpha) @ 60 Minutes (Boil)
1.3 g/L East Kent Golding (4.7% Alpha) @ 20 Minutes (Boil)


Single step Infusion at 67°C for 60 Minutes. Boil for 60 Minutes

Fermented at 18°C with Wyeast 1968 - London ESB Ale

 

[peebee]

Used 1968 once. Used starter (always do) aiming for a low-ish pitch rate (i.e. under-pitch for some people), 5 month old pack. Beer had an OG of 1.041, mashed at 67C. Down to 1.014 in two days, slowly crept down to 1.010 over following week. 75% apparent attenuation.

That was over two years ago. Never used it again since. So if it didn't work for you, don't worry about, just don't use it again (as I haven't). No great loss, I don't think you'll be missing out on anything.