Odd ESB brew...

[Zymurg]

Ok, I just switched to a SS conical system and maybe I changed too many techniques at once. Here's what I did.

I made an ESB and wanted it full bodied.
I mashed at 66C for 60 minutes.

I used a stir plate for the first time with a Wyeast 1968 London ESB

OG was 1.051

I fermented in the conical at 19C for 10 days.

I pulled the trub after a week - it was like clay! There was about 3 cups of it.

I transferred it to a carboy last night, the SG after 10 days was 1.032.

Seems quite high. Did my yeast drop out or was it because of the high mash temp? Should I repitch with some Safale S-04 and see if it continues?

Maybe some experienced brewers have some ideas for me.

Thanks,

 

[BrewerBrad82]

It does not look like your mash temp was all that high, 66C equates to ~151F which is relatively low. A mash at those temperatures will favor beta amylase activity and you should end up with a pretty fermentable wort.

1.032 sounds quite high for that amount of time in the fermenter. How did you measure the gravity? Did you use a hydrometer or a refractometer?

 

[botigol]

You didn't mash high; 66C ~ 151F, so you'd be heading toward light-bodied, not full. Since it wasn't the mash, the 'why' would only be speculative, but, yes, I would pitch some S-04 in order to try to get to full attenuation. At the minimum, rehydrate the yeast before pitching; the little alcohol that is present will work against your effort.

 

[jafo28]

1968 is a very high floccing yeast. It may not have completed the job and just flocced out. I think I read here once that you might have to rouse the yeast a bit to get it to finish where you want. Not sure if that was the case here.

 

[MrFancyPlants]

I would vote for a re-pitch, or pitch some pacman to take over.

 

[Zymurg]

It does not look like your mash temp was all that high, 66C equates to ~151F which is relatively low. A mash at those temperatures will favor beta amylase activity and you should end up with a pretty fermentable wort.

1.032 sounds quite high for that amount of time in the fermenter. How did you measure the gravity? Did you use a hydrometer or a refractometer?

I used a refractometer

 

[BrewerBrad82]

I used a refractometer

Bingo! Refractometers become significantly skewed when measuring samples with alcohol present, as alcohol throws off the refraction index that refractometers are calibrated to. Try out this calculator and see what you get:

http://www.northernbrewer.com/learn/resources/refractometer-calculator/

Do you have a hydrometer? If so, draw another sample and use the hydrometer - that reading should closely match the output of the refractometer calculator.

 

[Zymurg]

It does not look like your mash temp was all that high, 66C equates to ~151F which is relatively low. A mash at those temperatures will favor beta amylase activity and you should end up with a pretty fermentable wort.

1.032 sounds quite high for that amount of time in the fermenter. How did you measure the gravity? Did you use a hydrometer or a refractometer?

I used a refractometer. It read 6 Brix

 

[BrewerBrad82]

I just ran those numbers, and the corrected gravity is actually 1.019. Still a little high for that yeast, right now you are at ~63% apparent attenuation, which is a little low for that yeast. So 1.051 to 1.019 would equate to an ABV of 4.2%

 

[BrewerBrad82]

I used a refractometer. It read 6 Brix

Ok, that changes things... 6 brix is 1.024. SO, when I run those numbers again to correct for the refractometer error I come up with 1.007 as your final gravity.

Thus, 1.051 to 1.007 corresponds to ~86% apparent attenuation (quite high for that strain) and your ABV would then be 5.8%.

I would still check the final gravity with a hydrometer just to be sure...

 

[Zymurg]

It does not look like your mash temp was all that high, 66C equates to ~151F which is relatively low. A mash at those temperatures will favor beta amylase activity and you should end up with a pretty fermentable wort.

1.032 sounds quite high for that amount of time in the fermenter. How did you measure the gravity? Did you use a hydrometer or a refractometer?

I used a refractometer. It read 6 Brix.

OK! My conversion was wrong!
I checked several sites for refractometer conversions...I had forgotten about the problem with dissolved alcohol in refractometer readings.

With an OG of 1.051 6 Brix converts to 1.008.
Looks like it has completed just fine!

I tasted the warm flat beer and it was pretty good!

Time to keg it!

Thanks for your replies, if you change a lot of things at once it can get confusing!

 

[BrewerBrad82]

Im glad its all worked out, enjoy your ESB!

 

[Zymurg]

Yep, I'm going to double check it with my hydrometer when I get home.

Thanks!

Here's the recipe:
View attachment Honey ESB.bsmx