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General Category => Yeast and Fermentation => Topic started by: timmyr on August 09, 2010, 03:09:26 am

Title: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 09, 2010, 03:09:26 am
Hmph. At 4-weeks, both 5-gal batches of a 1.059 OG Oktoberfest have settled at 1.020. 66% apparent attenuation. Both pitches were on target (one WLP820, one WLP833) and a little on the high side for the Mr Malty calculator and I oxygenated both worts for about a minute well prior to pitching then just after pitching. Both taste good (but will improve I assume as they cold condition).

I know I could post all the mash details, etc., but wondered if anyone had experience with theses yeast strains/lagers and whether they trickle down those last 3-4 points over 4-6 weeks of lagering?
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: wingnut on August 09, 2010, 03:40:39 am
Timmyr,  I have not had any problems with either yeast attenuating down.  Yes, tweaking the mash schedule will have an effect on how low you can go with attenuation, but as long as you are following a normal  Oktoberfest recipe, you should have no issues getting the listed attenuation.

In my process, as fermentation begins to wind down, I warm the beer up to 65F.  This encourages the yeast to finish out the last little bits, and since all the replication is finished, there are very little off flavors in the beer.  If you did not perform this step, then maybe the yeast does not finish out the last little bit.   You may want to agitate the yeast a bit at a warmer temperature and see if you can get the last few percentage points to drop down.  However, if your beer tastes OK, you may just want to let it go.

The other thing I do,  with this yeast (and this is well after the beer has reached final attenuation, so this will not directly help your problem), is after the fermentation is done, I swirl the carboy gently or lift and twist the bucket a few times.  Not a lot, but enough to get some of the CO2 to bubble a bit.   I have found that the two yeast you have selected, provide a bit more sulfur then I like, and I have found that by having a little more CO2 off gas, this scrubs the extra sulfur out as well.

Good luck, but I am afraid it sounds like you have a stuck fermentation, but not a very serious one! 
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 09, 2010, 03:46:00 am
Thnx...it is not a serious stuck ferment.  I did raise to 62F for 4 days and fermented the rest of the time at 50F.  I sort of question my hydrometer (maybe some CO2 in solutiuon???), because it does not taste overly sweet, but who knows how well calibrated my palate is.  It is now sitting at 36F racked to kegs for lagering.  I can pitch more yeast or raise the temp if needed I suppose.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: animaldoc on August 09, 2010, 09:52:53 pm
Try taking a small sample and keep it at warm room temperature for a few days and see if it drops -- sort of a forced fermentation to determine fermentability of your wort.  If it doesn't change, you're pretty much done and should look at your mash parameters as a potential cause.

I think it's more likely mash related as you got similar numbers with 2 different yeasts.

-- Scott
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 10, 2010, 02:34:37 am
Try taking a small sample and keep it at warm room temperature for a few days and see if it drops -- sort of a forced fermentation to determine fermentability of your wort.  If it doesn't change, you're pretty much done and should look at your mash parameters as a potential cause.

I think it's more likely mash related as you got similar numbers with 2 different yeasts.

-- Scott

Likewise, but suprising, since I started at 120F and rested for about 15-20 min then ramped up to 152F over 30 min or so, and held.  I expected a REALLY fermentable wort...I better check my notes.  The weird thing is it does not taste sweet at all like I'd expect a 1.020 FG beer.  The WLP833 is really dry-tasting.  After re-checking my hydrometer, I think the gravities are really 1.019 (WLP820) and 1.018 (WLP833)
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 12, 2010, 12:31:25 pm
Last night I gave the kegs a good shake and raised temp to 55F.  Hoping to knock it down 4 more points.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: lazydog79 on August 12, 2010, 05:56:59 pm
I brewed a 'Fest w/ 820 in June.  Trickling is the word for my fermentation.  I have finally gotten it down to 1.026.  I haven't heard great things about this yeast, but it's what JZ used in Classic Styles.  The consensus I have gotten from several sources is that it will make a good 'Fest if you have the patience and skills to get it to do its job.  Me, I think I'm going to try Saflager 34/70 next time around.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: gordonstrong on August 12, 2010, 06:53:45 pm
I didn't like the Oktoberfest strain; I found it too sulfury, but I dont like that flavor much in my beer.  On the other hand, the Ayinger strain is one of my favorites.  Not that surprising, since I like most Ayinger beers.  I make my Oktoberfest with the bock yeast, not the oktoberfest yeast; those are just the marketing names for the yeast. Ignore those and look at where they originated, and how they perform.

Wort composition plays a bigger factor in attenuation than yeast strain.  Pitch enough yeast, follow good fermentation practices, keep the yeast in their preferred environment, and most yeast will attenuate about the same.

If your beer tastes dry (lack of residual sweetness) then it is likely fully attenuated. Dry-but-malty is the impression you want in many of the German styles. If it tastes good for the style, don't worry about the FG reading too much.

If you want it to finish lower, mash more in the mid-140s and start with a lower gravity. Both of those would help. I often make German beers with a 145 rest followed by a 158 rest; the first so it attenuates, and the second so that it has some body. I wouldn't expect a 152 rest to give you super-attenuating wort; that's an average temperature.

Are you accounting for temperature when taking hydrometer readings? Is it calibrated? Did you shake the CO2 out of solution? Each of those could be messing with your reading.  For that matter, are your thermometers calibrated, and did you stir the mash enough that you had consistent temperatures throughout the mash tun? Those could have affected your mash, and hence your expectations.

But when in doubt, use your palate.  Sounds like your beer is good, so that should be enough.  Let it finish lagering, then go drink it.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 13, 2010, 01:12:36 am
Gordon - it was a pleasure to briefly meet you at NHC (at the BN/NB Anniversary Party I believe) and thanks for the detailed response.

So far,

- I do not like 820 either, but really do like the 833 (Bock)
- The beer does seem to taste dry, but I have a lack of trust w/rt my palate, I'll enter it in competition and get some objective feedback
- OG 1.059 (overshot target by 4 points) and doughed in to hit 122F.  From there I did a constant recirculation and direct-fired my tun to raise to 152F.  That took about 20 min I think..I anticipated a pretty fermentable wort (JZ's recipe) but this is my first lager
- I am correcting all hydrometer readings for temp and recalibrated in distilled water to double-check my readings.  I think my hydrometer may read about a point or so high, but that could be just recalibrating my eyeball


Thanks for the detailed feedback and congrats on your success at NHC...awesome. 

Hopefully I pick up some tips in Chicago this Fall.  I was the lucky AHA Siebel winner...and that was my first NHC attendance  :o  Maybe I can send you a couple bottles for comparison.

Cheers,

Timmy
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: gordonstrong on August 13, 2010, 01:22:26 am
See?  Help people out and good things happen in return.

Sure, send me a couple and I'll let you know what I think.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 13, 2010, 02:07:52 am
See?  Help people out and good things happen in return.

Sure, send me a couple and I'll let you know what I think.

Cool man.  No doubt...did not think I'd even make it when I booked the hotel last year while deployed.  Ended up rallying a buddy of mine who shares my love for good beer to join me and had a great 5-days (arrived on Tuesday)

I'll let you know when I have in in some bottles...can't pass up your offer or evaluation.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: lazydog79 on August 14, 2010, 02:23:07 pm
I didn't like the Oktoberfest strain; I found it too sulfury, but I dont like that flavor much in my beer.  On the other hand, the Ayinger strain is one of my favorites.  Not that surprising, since I like most Ayinger beers.  I make my Oktoberfest with the bock yeast, not the oktoberfest yeast; those are just the marketing names for the yeast. Ignore those and look at where they originated, and how they perform.

Wort composition plays a bigger factor in attenuation than yeast strain.  Pitch enough yeast, follow good fermentation practices, keep the yeast in their preferred environment, and most yeast will attenuate about the same.

If your beer tastes dry (lack of residual sweetness) then it is likely fully attenuated. Dry-but-malty is the impression you want in many of the German styles. If it tastes good for the style, don't worry about the FG reading too much.

If you want it to finish lower, mash more in the mid-140s and start with a lower gravity. Both of those would help. I often make German beers with a 145 rest followed by a 158 rest; the first so it attenuates, and the second so that it has some body. I wouldn't expect a 152 rest to give you super-attenuating wort; that's an average temperature.

But when in doubt, use your palate.  Sounds like your beer is good, so that should be enough.  Let it finish lagering, then go drink it.

As always, great insights Gordon!  Good point about the palate.  I thought mine still tasted a little sweet, but not as sweet as you would expect. 1.026 to taste.  I will admit part of my problem could be my attempt at a single decoctition I did.  The finished product is where the rubber meets the road!

What is the Ayinger strain sold under with Whit Labs/Wyeast?
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: gordonstrong on August 14, 2010, 02:39:18 pm
Quote
What is the Ayinger strain sold under with Whit Labs/Wyeast?

Sorry, I should have been clearer. The OP asked about WLP833 German Bock yeast -- that's the Ayinger strain; I know that for a fact.

I don't know if there is a Wyeast equivalent.  I've seen some data online that says WY2487 is the same, but without any proof.  Others have said this is from Hurlimann or Eggenberg, which might fit better given how some have described its profile.

Anyhow, I would just skip trying to find a Wyeast equivalent and use the White Labs version.  It's known, and it works.  Even with common heritage, the yeast strains can be different when obtained from different suppliers.  I can't get the White Labs 530 yeast to act the same as Wyeast 3787, for instance.  So I just use the Wyeast version.

You can try a lot of different yeasts, but I think it's probably more useful for you to use a smaller subset of them repeatedly so you can learn their characteristics and how they respond to different fermentation conditions.  Your goal should be a predictable outcome, so if you understand how the yeast performs, you'll be in a better position to do this.  For me, I have WLP833 picked as my "malty German lager" strain, but have used it in other styles where I want that same character (CAP, for instance).
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: bluesman on August 14, 2010, 03:04:49 pm
I recently made an Ofest using WLP830 with very good results (OG=1.052).

I used a single infusion mash at 152F and fermented at 48F.  It finished at 1.010 (80.7%attenuation).  The beer has a smooth medium body with a slight creaminess which I was surprised to find knowing it attenuated as much as it did.  This is a 2nd generation of WLP830. It also had a very nice complex malt and a firm bitterness with a low background hop flavor.  I really like the performance of this yeast in a fest bier.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: blatz on August 14, 2010, 03:10:48 pm
Anyhow, I would just skip trying to find a Wyeast equivalent and use the White Labs version. 

I think Hellabock (WY2487) is a seasonal (or VSS) release anyhow so its harder to find. 

Had many fantastic beers with 833, though I use 830 exclusively. Hard to go wrong with either of those.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: gordonstrong on August 14, 2010, 03:17:18 pm
Quote
I used a single infusion mash at 152F and fermented at 148F.

Do you find it difficult to maintain that fermentation temperature?  ;D

Quote
This is a 2nd generation of WLP830.

That's supposed to be the W34/70 strain, which was George Fix's favorite.  If I trust internet sources, it's also supposed to be the same as Wyeast 2124, which is another of my favorites.  I used to use it in my malty German styles until the Ayinger strain was released.  I'll probably try it again; I had been focusing on the bock yeast while I was learning it.  Time to rediscover an old favorite; thanks for the reminder.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: bluesman on August 14, 2010, 03:19:45 pm
Quote
I used a single infusion mash at 152F and fermented at 148F.
Do you find it difficult to maintain that fermentation temperature?  ;D

Just making sure you were paying attention.   ;)

Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: bluesman on August 14, 2010, 03:22:03 pm

Quote
This is a 2nd generation of WLP830.

That's supposed to be the W34/70 strain, which was George Fix's favorite.  If I trust internet sources, it's also supposed to be the same as Wyeast 2124, which is another of my favorites.  I used to use it in my malty German styles until the Ayinger strain was released.  I'll probably try it again; I had been focusing on the bock yeast while I was learning it.  Time to rediscover an old favorite; thanks for the reminder.

Your welcome.  I also like using it for my German Pilsners.  It gets more attenuative through the generations.  I really like this strain.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: Thirsty_Monk on August 14, 2010, 03:46:30 pm
Quote
This is a 2nd generation of WLP830.

That's supposed to be the W34/70 strain, which was George Fix's favorite.  If I trust internet sources, it's also supposed to be the same as Wyeast 2124, which is another of my favorites.

I come across catalog from Brewing Science Institute and they say that
WY2124 = Weihenstephan 34/70
and WL820 = Weihenstephan 34/70

WL830 = Weihenstephan 206
and WL2206 = Weihenstephan 206

Here is the catalog:
http://www.brewingscience.com/PDF/prodlist/BSI_Product_List.pdf

Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: gordonstrong on August 14, 2010, 04:12:49 pm
Interesting.  I guess I'm not sure which sources to believe now.  So I'll just go by which I've used and what my palate tells me.  Again, I sometimes get different results from yeast that are supposed to be the same if I get them from different suppliers.

I like WLP833 and WY2124 in malty German styles and WY2206 in almost any lager, but usually the more attenuated ones.

I don't like WLP820 because of sulfur production.  I don't get that character in WY2124 or WY2206.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: tschmidlin on August 14, 2010, 08:07:56 pm
Here is the catalog:
http://www.brewingscience.com/PDF/prodlist/BSI_Product_List.pdf
It's too bad BSI stopped selling plates, as far as I can tell they have a lot of strains that Wyeast and White Labs don't make available.  I managed to get 4 of the CL strains and I have them banked, but it would be nice to get some other ones.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 15, 2010, 01:41:32 pm
No surprise the 833 is the Ayinger strain...it is clean and tasty.  Both kegs now sitting at 54F after being racked from primary.  Planning to check again in a week when I return from a short trip them take back down to 33F.

Based upon my initial tasting, the 833 is a clear winner over 820 so far.

I'll follow-up...and thanks for the clarification on the yeast strains.  Hope to have some fresh German lager this week.

Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: gordonstrong on August 15, 2010, 01:44:22 pm
Please post some side-by-side tasting notes when you do try them. I know it might be awhile; you do need to give them a chance to lager.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 17, 2010, 07:08:56 am
Please post some side-by-side tasting notes when you do try them. I know it might be awhile; you do need to give them a chance to lager.

Will do Gordon.  I plan to do just that as I am really curious how the two strains compare.  I have this feeling that maybe the 820 just needs a lot more time to hit its peak.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: bluesman on August 17, 2010, 10:28:10 am
I've used 820 many times and have found that I'm not a big fan.  It doesn't attenuate enough for my liking, however it may get better through the generations.  I think it does get better with some extended lagering time.  I haven't tried 833.  I will give that a shot on a Bock.

Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: ghumphrey on August 23, 2010, 04:07:12 pm
Hello all,

I'm having the same issues with attenuation in my Oktoberfest, but with a different yeast strain. I opted to use Wyeast 2633 - Octoberfest Lager Blend.

According to Wyeast, their Oktoberfest strain is a "a blend of lager strains designed to produce a rich, malty, complex and full bodied Octoberfest style beer. Attenuates well while still leaving plenty of malt character and mouthfeel. Low in sulfur production."

Unfortunately, after 3 weeks in primary (2 at 50 degrees F and 1 at 60 degrees F), I'm at 69% attenuation. The yeast's purported attenuation range is between 73-77%.

Has anyone had any similar issues with this yeast? I'm not sure of the source. If anyone has info, please post.

As far as fermentablity of the wort, I did a triple decoction, so I don't think that it's an issue (see the brewing log (http://brewlog.zkdigital.com/index.php?page=brewBlogDetail&filter=geoff&id=198) for the recipe)

Based on what I've read in this thread and from other sources, I have some options:

Thanks,

Geoff
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: wingnut on August 23, 2010, 06:40:38 pm

Based on what I've read in this thread and from other sources, I have some options:
  • Gently swirl the carboy to get yeast back in suspension and wait it out.
  • Ramp up the temperature to 65 degrees F to get the yeasties to consume the last of the sugars, swirl, and wait it out
  • Take a sample and do a "forced fermentation" to see if the are, indeed, any fermentable sugars left.
  • Add a fresh inoculation of an attenuative yeast like US-05 or WLP001, swirl, and wait it out.
  • Rack to a secondary to see if any further fermentation will occur. If not, cut my losses.
Thanks,

Geoff

One you Rack off the yeast cake, your done. (In my experiance).  What was the OG and SG so far?
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: bluesman on August 23, 2010, 06:49:50 pm

Based on what I've read in this thread and from other sources, I have some options:
  • Gently swirl the carboy to get yeast back in suspension and wait it out.
  • Ramp up the temperature to 65 degrees F to get the yeasties to consume the last of the sugars, swirl, and wait it out
  • Take a sample and do a "forced fermentation" to see if the are, indeed, any fermentable sugars left.
  • Add a fresh inoculation of an attenuative yeast like US-05 or WLP001, swirl, and wait it out.
  • Rack to a secondary to see if any further fermentation will occur. If not, cut my losses.
Thanks,

Geoff

One you Rack off the yeast cake, your done. (In my experiance).  What was the OG and SG so far?

Unless there is some yeast remaining in suspension. 

As I understand it...some Germans breweries will rack off the primary yeast at 75% attenuation and cold age the beer allowing it to slowly and fully attenuate acheiving that "distinct taste" which we  all strive to achieve.  I have yet to try it but I am planning to do so soon.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: ghumphrey on August 23, 2010, 06:52:06 pm
Quote
One you Rack off the yeast cake, your done. (In my experiance).  What was the OG and SG so far?

Thanks wingnut. My OG was 1.058 and the latest reading I have is 1.018.

Since my post I've been thinking. Dangerous practice, I know, but nonetheless, I've concluded to ramp up the temperature to 65 degrees F and swirl. However, I'm still open to any other ideas...

Geoff
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: tschmidlin on August 23, 2010, 07:23:34 pm
Quote
One you Rack off the yeast cake, your done. (In my experiance).  What was the OG and SG so far?

Thanks wingnut. My OG was 1.058 and the latest reading I have is 1.018.

Since my post I've been thinking. Dangerous practice, I know, but nonetheless, I've concluded to ramp up the temperature to 65 degrees F and swirl. However, I'm still open to any other ideas...

Geoff
I think that's a good idea, but some of your options aren't mutually exclusive.  I'd take a sample and get it up to ~75 or even higher, see if it finished out.  And you can add some more yeast to the sample if you have some lying around to do your forced ferment.  And you can do it while you wait for the rest of the beer to finish at 65F.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: wingnut on August 23, 2010, 08:00:32 pm
Geoff,

Take a drink of the beer... yes, 1.018 is on the high end, but I have medaled quite a few times with a FG of 1.018.  If it is not too sweet, then I would not mess with it. 

If it needs some help, I would force a small sample and see if you can drop a couple more points (raise temp, add yeast to the small sample, etc) and establish that there is indeed more fermentables left in the beer.  If you cannot get it down, then don't stress the whole batch by forcing it.

If you do get it to drop a few points, then you may try the technique that worked on the whole batch, or try to krausen the batch.  To krausen, I would rack the 1.018 beer off the yeast cake, make another similar or lighter beer, and put that on the yeast.  Once that new batch gets rocking, I would grab some of the beer and top-crop yeast (if possible) and put that into the 1.018 beer and see if you can get the last few points to go down.  The key is to have actively fermenting yeast, and not add priming sugar until the points have been dropped. 

My fear with adding some S-05 or other yeast that is not present in your base beer, is that it may add character that is not desirable.  If you can keep with the same yeast strain, your results will be more repeatable.

Good luck!
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: ghumphrey on August 23, 2010, 09:35:41 pm
My fear with adding some S-05 or other yeast that is not present in your base beer, is that it may add character that is not desirable.  If you can keep with the same yeast strain, your results will be more repeatable.

Agreed. I'm going to wait it out for another few days. I have a similar Bavarian yeast in storage, if my FG hasn't budged, I'll consider using it to bring things down, possibly using the krausen technique.

Thanks for the help!
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: timmyr on August 26, 2010, 12:16:38 pm
UPDATE:

After 11 days at 54F I think my gravities are still about the same (MAYBE a point drop).  However, the WLP820 has started to mellow out.  Since both batches are in kegs, they have slightly carbonated which is a clear indicator that the yeast that moved over from primary still have some energy left in them.  I am simply going to age a little longer at 54, depressurizing the kegs daily then drop to 33F and carbonate/lager for 2--6 weeks.  I am sitting around 1.019 on both batches and neither taste overly sweet IMHO.
Title: Re: Oktoberfest Gravity (WLP820/WLP833)
Post by: ghumphrey on August 30, 2010, 09:43:59 pm
My fear with adding some S-05 or other yeast that is not present in your base beer, is that it may add character that is not desirable.  If you can keep with the same yeast strain, your results will be more repeatable.
Agreed. I'm going to wait it out for another few days. I have a similar Bavarian yeast in storage, if my FG hasn't budged, I'll consider using it to bring things down, possibly using the krausen technique.

Thanks for the help!

UPDATE

I racked to kegs for lagering yesterday and the gravity dropped to 1.016. I took a taste and didn't find that it was cloying. Malty, but not cloying. Nice. After wiping the sweat from my furrowed brow and taking a deep, cleansing, breath, I set the kegs to lagering.

Tap date will be my birthday 10.10.10, the same day I'm brewing something special for the occasion: Ten Cubed (http://brewlog.zkdigital.com/index.php?page=recipeDetail&filter=geoff&id=165).  10 malts, 10 hop additions, and 10% ABV (not to mention 10X2 IBUs and 10 gallons).

Thanks to everyone for their words of advice.

Geoff