Yeast Repitch Advise

[RmikeVT]

Simple questions w/ hopefully a simple answer; famous last words. I brewed a 11.5g batch of 1.056 Oatmeal Stout, mashed at 153 F. I split the batch tossed re-hydrated S-04 into one and re-hydrated Mangrove Jack Newcastle Ale M03 into the other. Aerated w/ pure 02, pitch temp was 65. Full Krausen with in 24 hours, temps up to 66 or so. Anyway, after 36 hours the mangrove jack yeast pooped out. The S-04 chewed away and I can tell its still finishing up. The M03 - nothing.

After pitching I've read the M03 is pretty much a dud yeast and under-attenuates everything. People can't get smalls beers below 1.020. I took a hydro last night and this morning and its 1.020, all the while the s-04 is chewing away.

In 30+ batches I've never had a yeast problem, so I was thinking about pitching so S-04 or 05 or notty to finish the beer out. Is there a technique for pitching a second pitch into beer? Can I just re-hydrate and pitch, or can I dump the dry yeast right in. Do I need to make a starter to get the yeast "Active". Just want to hear some thoughts.

 

[dlester]

My guess is you need to do a starter: Although I'm sure a lot of people are going to say just throw it in. However, I would guess that you need to get the yeast some nutrients, 02 and time to start building their outer skin (forgot what you call it). Your not going to get that in a fermenting wort. Under attenuation and poorly maintained yeast are going to drive the diacetyl off flavors often described as a butter or butterscotch flavor.


Cheers,

 

[Copbrew133]

Give it another 36. If nothing, then rehydrate and pitch. Haven't used the MJ yeast, so thanks for the post.

 

[RmikeVT]

Give it another 36. If nothing, then rehydrate and pitch. Haven't used the MJ yeast, so thanks for the post.

I used their West Coast yeast and was very pleased with it. Seemed to Flocculate a little better than US-05, but aside from that no real difference. I've found a few post on the interwebs that indicate that the M03 just isn't up to snuff. I would never use again. I do everything to give my yeast a fighting chance and have never had a problem. I create starters when needed, re-hydrate dry yeast according to the method in Yeast, often times use nutriend in the boil.

 

[RmikeVT]

pitched a re-hydrated packet of Nottingham two nights ago. I didn't really notice any pickup in activity but I could have missed it overnight or while I was at working. I was only hoping for it to drop another couple points. I could take a hydro reading to check but at this point "it is what it is." I don't usually mess with my beers once I put the bung and airlock as I hate exposing it to potential bugs. I guess I will find out what the FG is when I keg it. I will continue to update the post for posterity.

 

[BigFloyd]

As you are seeing, pitching more yeast into a beer that has gone from 1.056 to 1.020 usually doesn't do anything but make it more yeasty. At that point in the process, even a small starter pitched at high krausen isn't likely to result in much, if any, gain.

I suspect that MJ Newcastle ale is similar in character to Windsor. Takes off fast, done in a couple days and fairly low attenuation with residual sweetness. What's the grav on the S-04 batch?

 

[RmikeVT]

As you are seeing, pitching more yeast into a beer that has gone from 1.056 to 1.020 usually doesn't do anything but make it more yeasty. At that point in the process, even a small starter pitched at high krausen isn't likely to result in much, if any, gain.

I suspect that MJ Newcastle ale is similar in character to Windsor. Takes off fast, done in a couple days and fairly low attenuation with residual sweetness. What's the grav on the S-04 batch?

So it appears to be the brewer not the yeast. I pulled a sample of the Mangrove Jack NewCastle M03 after a few more days and I was looking at 1.024 and the S-03 was 1.022 (measured with hydrometer, prior I was using my refractometer and found it to be out of calibration). Both finished way high. I added a 1/2 lb of turbinado and 1/2 lb of table sugar (boiled in a pint of water) to the Mangrove Jack. I calculated it out and should see a .008 drop in FG, which would put me in the ball park. If it works out I will do the same for the S-04 batch. I hate messing with my beer like this, but I just can't imagine an oatmeal stout starting at 1.056 and going down to 1.022/1.024 to be very good. Adding the sugar keeps me under the 10% simple sugar as part of grain bill and maybe the turbinado will add some complexity, it definitely had a roasty molasses taste before I dumped into the fermenter.

I brewed again this weekend and think I figured out my issue. I recently upgraded brew kettle & burner but not my mashtun. I have been pushing the limits of my 10g cooler mashtun with 11.5g batches. Anyway, I think I am getting big temperature differences in my mashtun and can really only measure temp in top 2 or so inches of the mashtun, while the whole thing is filled. Anyway, upgrading to a 70qt Coleman Xtreme, I never had a problem with mashtemp and attenuation with 6g batches, I just think I am pushing the 10g tun past it limits.

 

[duboman]

Also be sure to calibrate your thermometer, if its off you could be mashing at a higher temp than you think creating a less fermentable wort

 

[RmikeVT]

If anyone is following this thread, I just kegged the Oatmeal Stout I was having trouble with. It got down to 1.017 ish. So, the addition of US-05 and Sugar definitely dropped it a few points. From my math the Sugar probably dropped it a point or two and the US-05 and time must have been responsible for the last 3-4 points. The beer is good.