OG/FG/Yeast attenuation/ Priming prob?

Charlie W

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Hello all, First question here. I brewed 2 different batches of an APA using the same recipe. First batch was 1.054 OG, FG 1.016 using Safale S-04. Rehydrated according to instructions.
Second batch I had 1.052 OG and 1.010 FG using a pint of the washed yeast from the previous batch.

I primed both batches with 3.75 ozs priming sugar. The first carbonated, although low, which I didn't mind, more like an English style.
The second barely carbonated.... too much yeast affected the attenuation and I needed more priming sugar?

Any ideas would be greatly appreciated. Thanks guys, Charlie.
 
How big was each batch? How long did you wait? And what's the temp where they are conditioning.
Temp makes a big difference, you don't want them "cold". I typically wait three weeks before going to the fridge.
I'm usually using 4.5-5 oz for a 5.5 gallon batch (which is usually 52 bottles net) and have had good carbination in everything, all the way down to 1.005 FG.
 
5.5 gal to the primary. The first was 15 days @ 68 F and the second 13 days just to see how it's going. Now that I think about it, the first was bottle conditioned in my root cellar @ 61deg F. I bottle 22 oz's. I prefer a lower vol of CO2, more like an English style.

I was wondering if I pitched too much yeast? Is that possible? I may have to up my priming sugar. I was concerned because I used the same all grain recipe twice but used different amounts of yeast. Does washed yeast used 2-3 times attenuate more? Does it adapt?
 
well first if you wash yeast you need to make a starter to see if its alive or else you might just be pitching 3/4 dead yeast
 
I have heard that re used yeast can have a higher attenuation. having more attenuation shouldn't keep them from carbing the beer though. you may need to add a bit more sugar to get to the desired level, I'd check a priming sugar calculator to find out the right amount to use. the big question is how are the bottles being stored after you have bottled the beer? the colder the bottles are, the longer it will take for the yeast to eat the priming sugar and carb them. and don't put them in the fridge until they have carbed up or the yeast will go to sleep.
 
Charlie W said:
I was wondering if I pitched too much yeast? Is that possible?


First, Over pitching is possible, although in your example, you are probably fine. The results of an over pitch are that the yeast, being plentiful, consume all the available sugar with ease, and therefore the growth phase is limited. This results in a beer that lacks the fine character that that yeast would normally give to the beer. Some yeast have a lot of character (Belgian for instance), and some less or no character in their impact on the final beer. You are better off slightly over pitching then you would be under pitching. This probably wouldn't effect the prime as only a trace amount of yeast is necessary for priming. Temperature, good seal on the caps, making sure the prime is well mixed and distributed evenly in the bucket, TIME. These are more likely the cause.

Second, how you wash your yeast can have some effect on the primary fermentation. I mix the yeast cake with boiled and cooled water and allow it to stratify (20 min or so), then I siphon out only the middle layer. It usually has a light cream color. This consists mainly of healthy viable cells, good for a clean healthy ferment. The yeast on the bottom layer is mostly dead cells, and those that floculate and drop out quickly, both of which are of no use in the fermentation, as well as proteins, break material, grain bits, and hop particles. The upper layer is mostly water and the light dusty yeast that may ferment sugar, but tend to not drop out resulting in a cloudy beer, especially if used repeatedly. This also has minimal effect on prime.

Third, higher pitch rated can increase attenuation, as the yeast can consume all the sugar possible before giving up, and dropping out. That is why a proper yeast calculation is necessary if you want a specific attenuation. because the yeast then will have to work harder, and reproduce a few generations, and in the process will use up all the sterols, then drop out. Sort of like running out of gas, even though there may be some fermentables left. Yeast will consume the simplest sugars first, then work on the more complex sugars. When the work gets too difficult, and their energy runs low, they will quit. So if you want a extremely dry beer, one option is a large pitch. This will reduce you F.G. some, at the cost of yeast character.

Still, the prime of the beer is dependent on available sugar, temperature, and viable yeast. An over pitch would conceivably have an abundance of viable yeast cells, regardless of attenuation. Increasing the priming sugar will increase the carbonation level, if that's what you want, but be sure to allow plenty of time for the yeast to do its job. If you increase the prime rate to get a beer carbonated to your desired level at the two week mark, then If any sugar remains, it will be consumed, however slowly, and the carb level may not be what you desire at the one, or two month mark. Bottle bombs are an extreme result, but even a slightly over carbonated beer effects the taste. For the most part,it will make it sharper, more acidic and "spritzy". So you can raise the prime rate, but only after you have tested a your current rate in a well conditioned beer (two months at room temp).

Sorry to ramble on. Ive been drinking.
 
Thanks guys, I used the priming sugar calc they have here, guess I need to up it a little more. The bottles are stored in the pantry @67 deg.

"Third, higher pitch rated can increase attenuation, as the yeast can consume all the sugar possible before giving up, and dropping out. That is why a proper yeast calculation is necessary if you want a specific attenuation. because the yeast then will have to work harder, and reproduce a few generations, and in the process will use up all the sterols, then drop out. Sort of like running out of gas, even though there may be some fermentables left. Yeast will consume the simplest sugars first, then work on the more complex sugars. When the work gets too difficult, and their energy runs low, they will quit. So if you want a extremely dry beer, one option is a large pitch. This will reduce you F.G. some, at the cost of yeast character."

I think this is what happened. The fermentation was done after 60 hours. A real barnburner.

Thanks alot guys, good things to mull over. Charlie
 
You said you use 22oz bottles. I know size of the bottle effects carb levels. I have never used the priming calculator on this site, but it should give you the option to change bottle size when calculating.
 
skeevystoner said:
You said you use 22oz bottles. I know size of the bottle effects carb levels. I have never used the priming calculator on this site, but it should give you the option to change bottle size when calculating.

I use bombers quite often and have never seen a difference between those and 12 oz (long necks and short necks). The priming calculator doesn't have an input for bottle size.
But, this does make one think: fill level of bottles could have an effect on carbination.

It was also noted earlier in this thread the original poster washed the bottles with soap. As in dish soap? Seems I've read that this is not a good practice (I can't say why or where I read it). Might want to try using PBW for washing the bottles. (This probably wouldn't explain varying levels of carbination though)
 
MrBIP said:
It was also noted earlier in this thread the original poster washed the bottles with soap. As in dish soap? Seems I've read that this is not a good practice (I can't say why or where I read it).
Although I can seen where this might lead to problems, if rinsed properly, it most certainly shouldn't. I wash all of my bottles with dish soap, rinse well, and then sterilize again right before bottling. The only "problem" I have run into is, as someone already mentioned up-thread, varying degrees in carbonation due to improperly distributed priming sugar.
 
correct don't use soap, it leaves a film and can cause problems. use star-sans only if possible, you can put them in the dishwasher but no soap and high heat to dry
 
They now seem to carbonated a little more. I could probably do with a tad more priming sugar. Gern is right....time.

When I'm done with a bottle I rinse it out with hot water a few times, and store them upside down till time to sanitize with Star- San and bottle.
I think I'll pay a little more attention to making sure the priming sugar is more evenly distributed prior to bottling.
Thank you, guys.
 

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