Got a vial of WLP830 and i am making a 5l starter for a Vienna brewing this sunday. I want to make another 5l starter for a similar batch i’m doing a couple days later, but was wondering what the best way to grow. Should i decant the first starter and dump another 5l of wort on that cake then split that between the 2 batches, or pinch a little cake from the first starter and start anew?
I vote for “pinching.” In the first option, 5 L + 5 L does not equal to 10 L.
Assuming you hit maximum cell density on your first 5L starter, I don’t think you are going to grow more yeast by decanting into a second 5L starter.
The better question is why do you believe that you need a 5L starter? Are you making a large batch of beer?
Cuz Mr Malty said so. 5.6 Gallons of 1.052 recommends 5l using a stir plate/1 vial. Last Lager i did suffered i think because I under pitched.
First time a lesson, second time’s a fool.
That’s beyond ridiculous. No 5.6-gallon batch on the planet needs a 5L starter. A batch of that gravity and size is a 1-liter starter pitched at high krausen at best. I can start 5.6-gallon batch with 60B cells and produce an off-flavor-free beer. Do you aerate your wort? At what temperature do you start your wort?
What settings did you use to get to a 5l starter? The only way on a 5.6gal 1052 beer with that calculator is using a fairly old lager pack. Mrmalty IMO overshoots the viability drop off on yeast vials/packs. It also doesn’t take into consideration whether you are aerating/oxygenating the wort or whether you are pitching at high krausen.
i’d feel good with doing the 5l starter and split the cake for the two batches. good fresh yeast and plenty for both average size brews IMO.
I’m seeing the same results with a production date of today and continuous aeration.
When I plug 5.6g of 1.052 and 9/24 as production date, I get suggestion of 1 vial and 1.03L starter, unless I missed a detail somewhere…?
edit: missed lager, now it reads 2.06L
I get the same 2.06L when I’m at ale, simple starter. When I swap it over to lager, it goes to 4.12 L with 2 vials. That or 10.21L with 1 vial! (keeping it at simple starter throughout).
I see that now too, thought we were on continuous aeration. Simple does give 4.12L. I knew I must have been missing something, turns out it was 2 things
I gave up on pitch calculators. Too many variables to consider. I don’t poopoo them for an entirely new brew or yeast, but I have found that I usually need to tweak things on the following rebrews.
I’ve also quit using my stirplates, but thats because I am following the new trend of not following old trends. [emoji12]
Right there with you Jim. No more stirred starters for me, and just trying to get within 1 replication period of optimal pitching rate. I have been very happy with my results so far 8)
I don’t shake it like it owes me money… thats what I wasted money on Oxygen and a stone for. So I oxygenate, then shake till I’m bored of shaking (about 15 secobds). Anyway, it gets me more yeast than the stirplate and it smells totally fresh and tastey, as compared to rank yeasty stirplate stuff. Works for me.
All of my ales get 2L of 1.030 and one smack pack per 6 gallons, lagers get two of those per 6 gallon. Amounts subject to change when dialing in a specific recipe. Someone may say thats too much, and I would say yes it might be. But the effects of too much are far less noticeable vs too little. Though, one might want too little or too much (at least compared to a calculator) depending on desired effects.
Yeast calculators are about as useful as toilet paper when it comes to propagating yeast cells. Yeast cells are living organisms that behave differently in different environments. The only way to know how a yeast culture is going to behave in one’s brewery is to use it and take very good notes.
As I have said many times, the difference between a 1L starter and a 2L starter is approximately 90 minutes of propagation time, making the argument for a 2L starter when pitching normal gravity beer a non-sequitur. Now, the difference between a 1L starter and a 5L starter is log(5) / log(2) * 90 = 208 minutes, or 3.5 hours of propagation time. However, one is looking a step rate of 22 / 5 = 4.4 when pitching the cells from a 5L starter into a 22L batch of wort. It takes approximately log(4.4) / log(2) = 2.14 replication periods to reach maximum cell density when pitching at that rate. In practice, we should step between 10 and 20 for most batches, especially if we plan to repitch the slurry. Pitching at a higher rate than that tends to lead to declining culture health, as the average cell age increases with each pitch.
The key to successful fermentation is to pitch enough healthy cells at the peak of their performance into well-aerated wort to get the job done. The osmotic pressure difference between the cell contents and 1.056 wort is not high enough to cause dehydration and loss of turgor pressure, resulting in cell shrinkage and wrinkling of the cell plasma membrane as happens when one pitches a starter into 1.080 wort. Additionally, the solubility of O2 decreases as wort gravity increases (Henry’s Law). In essence, we have to pitch a higher number of cells when pitching high gravity wort because of cell loss coupled with lower growth rates and cell health due to lower gas (O2) solubility.
You lose me easily and frequently but that high gravity explanation is awesome. I did not know that. I knew it took more yeast, now I understand why.
Allow me to clarify:
Using Mr Malty,for 5.5 gallons of a 1.052 lager and 1 vial of WLP830 manufactured 8/28/15, Jamil’s calculator recommends building 4.97 Liters of 1.030 starter. 400 billion cell count.
To be clear i am not planning on dumping the full 5 liters into my wort! The Starter fermented out in about 24hrs and is resting comfortably at 45* settling out. Sunday afternoon I’ll decant and pitch the cake along with about.3l spent wort.
Now I’m no expert but I’ve been brewing lagers for roughly 9 years. And when i wing it and underpitch (ie. a 1 liter starter) Yeast gets stressed, my lagers come out sweet and under-attenuated. Conversely, When i use relatively fresh yeast, build a starter following Mr Malty’s guidelines aerate, pitch low and come up to fermentation temp, I get very clean lagers. I cant argue the explaination below. after reading it several times, walking away, then reading several more times it does make sense. I also know what works for me and what dont. Guess I’m just stupid
A big part of your problem is that you are letting the starter ferment out. One should never let a starter ferment out. That’s a no-no when propagating yeast. A starter is not a small batch of beer. It is a propagation medium, and should be treated as such.
If you pitch at high krausen, you can can cut your cell count in half because the cells are still in the exponential phase with non-depleted ergosterol and unsaturated fatty acid (UFA) reserves. Allowing a starter to ferment beyond high krausen results in unnecessary ergosterol and unsaturated fatty acid (UFA) depletion because all reproduction beyond that point is for replacement only and mother cells share their ergosterol and UFA reserves with all of their daughters. It also results in the yeast cells undergoing survival-related morphological changes that have to be reversed before the cells can start to take in nutrients and expel waste products through their cell walls. Quiescent cells place a higher initial O2 load on the wort.
Do you happen to be using a stir plate? If so, that is part of your problem. Stir plates subject yeast cells to shear stress.
I do not understand a lot of the technical specifics, but after much thought I must agree. It makes sense that after you grow a bunch of yeast, then they go back to sleep, then wake them back up…
So, in the future, I will try growing 1l of 1.030, and pitch the whole liter at high krausen/no stir plate. What temp. do you recommend for a lager starter?