^^^^This.
I use the same rationale when I re-pitch a slurry. As Denny says, less room for error and I don’t taste any rubberiness from autolysis.
So the kveik looks like it’s almost done. Gravity has dropped about .1 brix/day for the past three days. It looks like it’s going to finish right around 10 brix. The last batch with this same yeast finished at 8 brix. My OG was only .5 brix higher on this batch so thought it would finish at 8.5 or close to it. Is finishing higher typical of re-pitched yeast?
Were you a wine maker before you start to brew? The reason I ask is that Brix is the scale that wine makers use. Brewers use Specific Gravity or Degrees Plato. Degrees Plato and Brix are basically the same thing when the solvent is water.
Not a winemaker. I use a refractometer for measuring gravity since it only needs a small amout of wort. Someone told me not to use the SG scale on it as it wasn’t accurate. Not sure if they were talking about a specific manufacturer or what. I’ve checked my refractometer over it’s range against a converter (https://www.brewersfriend.com/refractometer-calculator/) and it seems to be spot on (Brix <> SG @1.0 ) so not sure what the issue actually is.
What if I told you, I only take original and terminal gravity readings and that is only for quality control reasons? A yeast culture will tell you when it is finished fermenting. if you are using an airlock and the temperature of the green beer is not rising (hence, allowing CO2 gas to come out of solution), airlock activity will slow to a crawl, eventually stop and the green beer will start to clear. Far too many amateur brewers have adopted crash cooling in order to get a culture to drop out of suspension. Crash cooling may be necessary for professional brewers in order to meet production schedule demands, but it is absolutely an unnecessary step for amateur brewers. The culture will floc and drop clear when it is done. Some powdery (i.e., low to non-flocculating) strains take longer to drop than others, but they will drop if given enough time. If a culture is in suspension, it still has work to do; therefore, patience is a virtue.
By the way, anyone with a pulse has heard AB’s claim that Bud is beechwood aged. However, in this case the beechwood adds no flavor because the aging process is based on the old practice of using beechwood to clarify beer. The aging tank (a.k.a. chip cask) is filled with boiled beechwood chips. The purpose of the chips is to increase the surface area on which AB’s yeast culture can settle. That is their sole purpose.
Man, you really have your info nailed down. Yep, I’ve heard the AB claim but honestly never gave it much thought…heh… One of those beer commercials used to make a big deal out of “krausening” or claimed their beer was “krausen’d” as well :o
As far as CO2 coming out of solution, are you referring to airloc activity in general or something more specific? My understanding is that changes in air pressure and/or ambient temp changes can affect airloc activity even when no fermentation is happening. Maybe there is more to that?
All my beers thus far have been slighlty hazy but I think that’s due to my dry hopping in the chilled keg, or chilling in general. Could be from suspended yeast but I guess I don’t mind so much. As long as it’s not plugging the dip tube ;D
I have read that they don’t even use beechwood, but aluminum spirals, for the same reason. I’m willing to believe that may be apochryphal.
I am attempting to differentiate between dissolved CO2 coming out of suspension and CO2 actually being produced. The beauty of using a clear fermentation vessel is that it is easy to determine when fermentation is complete because there is a color change, starting at the top, when fermentation is complete. The thing to remember is just because a batch has reached terminal gravity does not mean the yeast culture is done doing its job. Most cultures will continue to consume metabolic waste products for a period of time after it appears that fermentation is complete. That is why cold crashing as a practice is non-optimal for amateur brewers who have the gift of time. I have never had a cold-crashed beer that tasted as good as one that was allowed to settle on its own schedule. Amateur brewers do not need to cold crash because we are not beholden to bean counters. Our hobby is not driven by profit and loss.
Once the yeast activity stops I package because there’s no O2 protection after that point. When I see a flatline on the data logger, I package and cold crash. I don’t want the beer sitting in a fermenter any longer than it takes to actively ferment potentially exposing it to O2 pickup.
However, O2 pickup is a non-sequitur while yeast cells are still in suspension. One of the reasons why bottle-conditioned beer stores better than filtered and bottled beer is because bottle-conditioned beer has an active yeast culture that continues to scrub O2 as long as it is in suspension.
I thought the yeast had to be active. Thx for the clarification. Good to know it just has to be present.
I recall Dr Bamforth saying if a beer is oxidized run some yeast thru it. If you say it doesn’t have to be active his statement makes even more sense.
I have a few recent brews that seem to corroborate this statement. I ferment in kegs with a spunding valve on the gas poppet. My last few batches have been chilled and kegged as soon as there was no increase in pressure on the valve for at least 2 days, rather than waiting my usual 10-14 days to package. I’m finding that these batches taste more muddled and flat than usual.