Do we all massively under pitch?

[Tomp]

Do we all under pitch?

Just been using the Beersmith yeast calculator and comparing the suggested number of packs as per the Whitelabs recommendations for a 23 litre batch.

Whitelabs suggest 1 pack for a beer of 1061 as and a 1 litre starter. This is what I intended to use - until I ran it through Beersmith....

Beersmith suggests 3 packs with 3.7 litres of starter with 100 billion cells (as advertised by Whitelabs)..... WTF!!!

I presume if you follow the Beersmith guidance, it will ferment out faster? Does this mean Beersmith is intended for more 'commercial' operations where fermentation time needs to be speeded up, where us home brewers aren't in such a rush?

What benefit a quick fermentation? Discuss...

[Kev888]

In a homebrew context many of us estimate these things rather than quantifying them more directly, so there will be a little variation in opinion, some of us may over pitch a little, others (probably fewer) may under-pitch - though not always accidentally. Whitelabs seem quite optimistic of their yeast viability with age and transport, too - in general people seem less trusting of this. BUT that is an enormous and abnormal difference in the OP, which IMO won't be accounted for by subtleties in decent estimates.

There are some fundamentals which 'will' have such a big effect though, so I strongly suspect you (or your sources) may not be comparing like-for-like conditions or assumptions. You need to make sure the estimates are based on the right parameters; key ones include viability of the yeast (in the absence of a better home-brew method, often estimated from its age), type of starter method used, lager or ale yeast and desired pitching rate for the volume and gravity. If all these things are the same then the suggested estimations should be rather closer, if they are any good.

EDIT: I struggle with any of my methods to arrive at 3x packs in nearly 4L, so that seems quite a lot. EDIT2: But then I (and I suspect most) would not do this in any case, rather we would step up the starter rather than buy/pitch many more packs to make one big initial starter.

[Bigbud78]

This is the calculator you require http://www.brewunited.com/yeast_calculator.php

Its great as It works out your overbuild for your next starter

[Tomp]

This is the calculator you require http://www.brewunited.com/yeast_calculator.php

Its great as It works out your overbuild for your next starter

Thanks. Just what I was looking for. Nice and simple to use.

[McMullan]

I suspect many home brewers under pitch yeast. The viability of stored yeast declines over time, depending on a number of factors. Those calculators are guesstimates. They don't always guess right. They hedge their bets by recommending large starter volumes, which, apart from consuming extra resources, open another can of worms.

[seymour]

Yes, yes, undoubtedly yes.

[PeeBee]

"Do we all massively under pitch?".

Including everyone in that statement is most definitely wrong. Try this for a bit of bedtime reading:

viewtopic.php?f=2&t=79509

Okay, I may have let it get a bit warm (by all of 2 degrees C), I may have over-oxygenated (bad guessing because of lack of guidance). But I believe the biggest culprit was over-building starters because of under-optimistic starter calculations. My conclusion was a little under-pitching (as determined by most popular calculators) need not be a big issue. But a little over-pitching might possibly be a serious issue. Massively under-pitching might mean fermentation never gets started (or is very slow) and a brew is lost, but don't make the mistake of over-pitching to compensate for mistrusting the available guidance.

All the uncertainty is made worse by the strain of yeast no doubt having an impact, but the popular calculators won't account for specific yeast strains.

Such a difficult to tie down subject means there's a dearth of good guidance and lots of space for dubious guidance.

[McMullan]

There is very little 'uncertainty', as long as you pitch a healthy yeast culture. Enjoy those calculators... a scam supporting a scam. Belief means everything...

[johnnyboy1965]

As Homebrewers it is impossible to count yeast cells.
What I do is, I measure out by volume the yeast that I have harvested
When I bought a WhiteLabs yeast i noted how much (by volume) yeast there was. Going on their recommendations that should be enough for a 23li brew.
I rinse the "slurry" twice, so Im pretty happy that I have only harvested yeast not slurry. I then put the same ammount into test tubes.
I then make a small "starter"...500ml...This is not a actual starter, more just to prove the viability of the yeast.
I do all this on brewday and then pitch at the correct temp.

[McMullan]

A number of home brewers, including myself, use microscopes to assess cell counts, as well as cell viability. The approximations are comparable to what most labs would report. It's a fairly straight forward procedure. It doesn’t have to be a precise measurement. It’s beer, not a life-threatening condition. As long as you have a ball-park number of healthy cells ( about 6 million per ml for a standard brew), you’re good to go. Being slightly under or over makes little difference, whatever the exact number might be for a given strain? Assuming sufficient healthy cells are pitched, it’s wort conditions that then matter. Temperature, of course, fermentability and and nutrients, especially oxygen. The final cell count in the fermenting wort is determined by wort resources, especially initial O2 levels, assuming sufficient cells were pitched. Personally, I recommend the use of yeast slants/slopes (BrewLabs in the UK). A 500ml starter produces sufficient cells for most brews. Make two starters if making a big beer or a lager. Harvesting and reusing yeast without making a starter, i.e. re-pitching within a few days, is fine, if using established techniques, e.g. top cropping or a variation of that, like IPA's method. However, fresh yeast are required after several harvests, to avoid the risk of losing a brew, after a long day preparing wort.