decided to live on the edge and do my first batch using the yeast cake of the previous batch. its a 1.060 pale ale with wlp090 and im making another round of it at the 2-week mark when i keg it.
looking for advice on how much cake to use - just use it all or just a portion? pro’s. con’s.
thanks
For a beer that size I’ve had good luck using a third of the cake. Pros - quick, strong fermentation. Cons - as long as your sanitation was good, not many.
I like the picthing calc at www.mrmalty.com for slurry repitching.
so if im using the mr.malty calc right - i give my carboy a good swirl, and then take about 3.5-4 cups of slurry and use that to rack the new wort onto?
I usually take my yeast from the bottom of my carboy or bucket or whatever I’m using and put it in a mason jar after a good swirl (you can add a little pre-boiled water if the slurry is too thick). Often it will take 2 quart sized jars. Then I will use the ml on side of jar to get close.
I use the calculator as a starting point and figure how much I need based on how well the yeast performed or how healthy I feel the slurry is.
4 cups is a TON of yeast - probably more than you have after fermenting 5 gal. Using the default settings, the mrmalty calculator says ~100 mL for a 1.060 beer.
Ive often thought I was over pitching on my repitches. If you look at how much is in a decanted 2L starter, compared to a full cup of slurry? It seems like too much. But then there’s trub to consider too. Ive been experimenting all summer, so all fresh starter pitches. But this winter when I up my production and go back to repitching, I think I’ll back off a bit.
Since we aren’t doing cell counts aS homebrewers, t all boils down to experience. If you see the pitching calc recommends 100ml, and you pitch 100ml and you have signs of fermentation in 12 hours you know you have pitched enough. If not, then you better pitch more.
The calc has a slide option for “non-yeast percentage” as well. It is not perfect but you can get close.
4 cups of yeast is a heck of a lot of yeast.
I think the most I’ve repitched was a cup and a half into an oktoberfest
When harvesting, I just take a gallon sized ziplock type Baggie to line a half gallon plastic pitcher (to make it easier to pour into the Baggie). Then I eyeball the amount from there. I do a lot of ten gallon batches of same ABV range lagers, so for those, I will re-pitch at the rate of about half of the original harvested amount; ales go at around a third or less. If the harvested yeast has sat for over a month, I typically will make a starter, but not always; sometimes I will just pitch a bit more than the fractions above. YMMV, of course, and bigger beers of any type require more yeast to complete the process without excessive stress.
Yeah so I see I need to adjust slurry thickness on mr.maltywhich is why it said 3-4 cups. When moved to thick its 1.5 range
so mission accomplished. i harvested about 1.25 cups of slurry and pitched into my pale ale brew . curious to see the difference in lag time vs my yeast starter with previous brew… that was 6 hours.
I bet it will run like a house afire! I am going to try scaling back a bit on my re-pitches to see if I get a little cleaner, less estery result on a few beers. But lagers still need a good healthy pitch compared to ales (except for the monster ales - they need a goodly pitch, as well).
Let us know how it progresses.
fermentation took off at 4 hours…here we go.
Not surprised. It usually goes like gangbusters using healthy slurry !
That’s most likely a significant over pitch, so no surprise there.
Edit: Assuming this is a <15 gal batch.
True enough - 4 hrs is very quick, Sean. I connected with the ‘quicker start’ part, but not the time frame. My bad - long week !
4 vs 6 hrs with a starter doesn’t seem much different. And my starter was certainly not aggressive.
sandiego super yeast wlp090 - always takes off fast for me.
so after 2 weeks and 3 consecutive readings, my final gravity was 1.018-this beer has always finished at 1.011-1.012 for me.
all things considered, mash temp 153F, ph 5.3, OG 1.060 and fermentation temp of 67-68F were all as they always are for this recipe. the only new variable was using the previous slurry vs. fresh yeast and starter.
Any thoughts on why the FG ended so high? got me hesitant on using the slurry ever again without knowing what may have happened.
I may have overpitched some batches as I said before, so I tried this weekend using the Mr. Malty calculator for a lager - I repitched in 2 ten gallon batches: 500 ml in each, as the slurry was very thin. It was cranking by the next morning, with visible krausen.
However, when I have “overpitched” (i.e., didn’t measure in any precise way), my finishing gravities were usually low (1.004 to 1.008), so I don’t know about the higher FG you are experiencing. Did you swirl the fermenter a little toward the end? For beers that are finishing high, I try to do that and have pitched some high krausen starter in those situations with some success.
Good luck with your beer. I wouldn’t give up on pitching slurries based on this one event, however.