I know this can't be the yeast and must be something in my process, but every time I use Dasnstar yeast I get pretty bad diacytl. It sucks because I really want to use this yeast as I love English styles. My system is dialed in so I'm not sure what else to do in order to prevent this. Suggestions?
Danstar yeast and diacytl
- Thread starter JDFlow
- Start date
Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:
COLObrewer
Well-Known Member
Without knowing anything about your process, I can offer only a few insights: Diacetyl from yeast is usually created during the early stages of fermentation, it can be cleared up using a diacetyl rest which is usually appx. 10 degrees F above the fermentation temperature. It can also be caused from infection, sometimes from unclean serving lines etc.
Here is what palmer says regarding diacetyl:
"Diacetyl is most often described as a butter or butterscotch flavor. Smell an unpopped bag of butter flavor microwave popcorn for a good example. It is desired to a degree in many ales, but in some styles (mainly lagers) and circumstances it is unwanted and may even take on rancid overtones. Diacetyl can be the result of the normal fermentation process or the result of a bacterial infection. Diacetyl is produced early in the fermentation cycle by the yeast and is gradually reassimilated towards the end of the fermentation. A brew that experiences a long lag time due to weak yeast or insufficient aeration will produce a lot of diacetyl before the main fermentation begins. In this case there is often more diacetyl than the yeast can consume at the end of fermentation and it can dominate the flavor of the beer."
Here is what palmer says regarding diacetyl:
"Diacetyl is most often described as a butter or butterscotch flavor. Smell an unpopped bag of butter flavor microwave popcorn for a good example. It is desired to a degree in many ales, but in some styles (mainly lagers) and circumstances it is unwanted and may even take on rancid overtones. Diacetyl can be the result of the normal fermentation process or the result of a bacterial infection. Diacetyl is produced early in the fermentation cycle by the yeast and is gradually reassimilated towards the end of the fermentation. A brew that experiences a long lag time due to weak yeast or insufficient aeration will produce a lot of diacetyl before the main fermentation begins. In this case there is often more diacetyl than the yeast can consume at the end of fermentation and it can dominate the flavor of the beer."
COLObrewer
Well-Known Member
If you are brewing a typical gravity beer there are ample yeast cells in any dry yeast packet. You can go to mrmalty.com to calculate the proper amount of yeast needed for a particular brew.
Echoloc8
Acolyte of Fermentalism
You could also just pitch two packets. Simpler and less time consuming than going to the trouble of a starter.
Or rehydrate: won't increase cell count, but it'll make sure they're awake and ready before pitching.
A Danstar Nottingham fan here myself. Hope you get it worked out.
-Rich
I also rehydrate.
I'm able to and do control temps. Chest freezer and Johnson control. My temp might swing 2 degrees in a really active fermentation.
I'm convinced it's the cell count. The first time it happened was in my first pumpkin ale. I tried to convince myself it was a characteristic of the pumpkin. Then I tried an IPA. My last attempt was an English pale. Diacytl, Diacytl, Diacytl.
+1 on rehydrating.
I suggest that you keep both of those in the low 60's for at least the first week. If you then step them up to 65-66*F for a week or so. That should give the yeast a chance to clean up and leave no diaceytl taste. Running Notty at 70*F is likely to cause some off-flavors.
Since you have a controller (a wise decision, btw), you can do something neat with Nottingham that has worked very nicely for me. For the first week, run it at 55*F. That's 2*F below its recommended range, but it has actively fermented there for me. After the week has passed, slowly step it up to 63-64*F and let it hang there until you reach FG. Finally, give it a couple of days to finish (like a D-rest) at 67* before you cold crash it. The result is very clean and lager-like with full attenuation.
I'm not a big fan of Windsor. It tends to take off fast, run hard for a couple of days, and then poop out well short of full attenuation. I like Notty much better.
