Pitching rate discrepancies between manufacturers and other calculators

[hoppyscotty]

Basically which to believe? I'm erring the side of the yeast manufacturers, but they tend to recommend a lower pitching rate compared to some other calculators...in particular looking at a current recipe I'm working on in Brewfather and the Brewfather calculator comes up with 4 packets of yeast and the Lalbrew calculator comes up with 3 packets.

Which to go for? Part of me thinks go with 4 but I don't want to overpitch for the sake of over pitching.

 

[AJA]

What are you making/ which yeast are you using?
In some styles overpitching is as bad as underpitching.

 

[DocAnna]

Basically which to believe? I'm erring the side of the yeast manufacturers, but they tend to recommend a lower pitching rate compared to some other calculators...in particular looking at a current recipe I'm working on in Brewfather and the Brewfather calculator comes up with 4 packets of yeast and the Lalbrew calculator comes up with 3 packets.

Which to go for? Part of me thinks go with 4 but I don't want to overpitch for the sake of over pitching.

It depends what you are brewing, both in terms of beer style and original gravity. So lagers and high gravity beers will require more yeast in general and the calculators will take that into account. It's also worth considering whether over or under pitching is going to be a problem, as for beers brewed at warmer ie ale temperatures, a single dry yeast pack will cover a standard 20-30 litre batch. For a lager brewed at cool temperatures then multiple packs are advised or even better use a starter. Last weekend, I added 1 litre from a 3 litre settled starter for a 23 litre batch of lager which was based on a calculator as the pitch rate is more important in such settings. Some other specific yeasts such as Philly Sour are pitch dose dependent, though a single pack again is suitable for a standard home brew batch size, but if brewing a small or larger batch will need to be adjusted by the manufacturer's recommendations.

 

[hoppyscotty]

It's just a 40 litre batch of an IPA with OG 1.060 using Lalbrew BRY-97 so a dry yeast so not as delicate a liquid ones. I'm erring on the side of just pitch 4 but I'm believe there are potential downsides to overmatching as well as under pitching.

 

[AJA]

That seems on the high side (1.1g/l) but still within the realms of reasonableness.
Some of the Lalbrew yeasts (e.g. New England) have a reputation on here for requiring higher pitch rates than comparable yeasts.

 

[DocAnna]

The data sheet for Lalbrew suggests 0.5 to 1g per litre and dry pitching, and since it is a yeast intended for biotransformation of hops, the pitching rate is not as generalisable as the calculators would suggest. I'd go with the manufacturer rather than the calculators in this case.

 

[hoppyscotty]

Thanks, my head said go with manufacturers recommendation, but just got me thinking why some of the other calculators come out with different values.

 

[Brewnaldo]

I have a question about starters which I guess can fit in here.....

If I dont have the needful to fit a 2 litre starter in (I dont have a decent flask that size) Do I get the same cell growth from pitching the yeast into a 1 litre started, letting it ferment out, then pitching the settled yeast into another 1 litre starter?

 

[dave_77]

I like the lallemand calculator as it seems to adjust the pitch rate based on yeast strain, temperature and gravity which gives interesting recommended pitch rates.

 

[DocAnna]

I have a question about starters which I guess can fit in here.....

If I dont have the needful to fit a 2 litre starter in (I dont have a decent flask that size) Do I get the same cell growth from pitching the yeast into a 1 litre started, letting it ferment out, then pitching the settled yeast into another 1 litre starter?

Not quite. The inoculation rate also impacts yeast growth, so when the second starter is settled out, and added to the second starter volume then the inoculation rate is low enough to suppress growth rate. This can be illustrated in Brewfather
For a 2 litre starter from a tiny 1 billion cells at 1.040 gravity will yield 392 billion cells
The same 1 billion starter split over two 1 litre starters will yield 333 billion cells.

However... this is all based on theory, assumes all your yeast floculates out and is transferred to the second starter, and you've been clever about making sure the second starter gravity takes account of the volume added from the first starter. In the real world, the yield is likely to be a fair bit lower than the calculation, but for the purposes of home brew the impact on fermentation is unlikely to be that significant due to the host of other factors that will determine yeast viability. The short version would be, no they aren't the same, but you'll still get more yeast from a two step starter than just a one step.

Personally after trying a couple of two step starters I asked nicely and my mother bought me a 3 litre Erlenmeyer flask for Christmas last year . She said it was the most unusual present she'd bought me since the nice stainless steel garden fork and spade from the previous year!

 

[Brewnaldo]

Not quite. The inoculation rate also impacts yeast growth, so when the second starter is settled out, and added to the second starter volume then the inoculation rate is low enough to suppress growth rate. This can be illustrated in Brewfather
For a 2 litre starter from a tiny 1 billion cells at 1.040 gravity will yield 392 billion cells
The same 1 billion starter split over two 1 litre starters will yield 333 billion cells.

However... this is all based on theory, assumes all your yeast floculates out and is transferred to the second starter, and you've been clever about making sure the second starter gravity takes account of the volume added from the first starter. In the real world, the yield is likely to be a fair bit lower than the calculation, but for the purposes of home brew the impact on fermentation is unlikely to be that significant due to the host of other factors that will determine yeast viability. The short version would be, no they aren't the same, but you'll still get more yeast from a two step starter than just a one step.

Personally after trying a couple of two step starters I asked nicely and my mother bought me a 3 litre Erlenmeyer flask for Christmas last year . She said it was the most unusual present she'd bought me since the nice stainless steel garden fork and spade from the previous year!

I dont recall ever getting bad results off of liquid yeast, but looking at the calculator on this site, its telling me for a lager, with a 100bn cell sachet manufactured today, I need 427bn cells. Its telling me that a 1 litre starter, then stepped up into a 2 litre starter STILL isn't enough yeast.

I'm not up for 2 stages and 3 litres of wort. It seems unreasonable

ETA.... Lallemand calculator tells me you need 3 packs of Diamond in a 23 litre, 1.050 lager. Never heard the like!!!!!

 

[DocAnna]

I dont recall ever getting bad results off of liquid yeast, but looking at the calculator on this site, its telling me for a lager, with a 100bn cell sachet manufactured today, I need 427bn cells. Its telling me that a 1 litre starter, then stepped up into a 2 litre starter STILL isn't enough yeast.

I'm not up for 2 stages and 3 litres of wort. It seems unreasonable

ETA.... Lallemand calculator tells me you need 3 packs of Diamond in a 23 litre, 1.050 lager. Never heard the like!!!!!

Yep, that's why I added that at the level of homebrew that the impact on fermentation is unlikely to be that significant due to the host of other factors that will determine yeast viability. Calculators need to be considered against the mathematical model data they are derived from that often have large margins of error ie best taken with a healthy dose of pragmatism.

 

[Brewnaldo]

Yep, that's why I added that at the level of homebrew that the impact on fermentation is unlikely to be that significant due to the host of other factors that will determine yeast viability. Calculators need to be considered against the mathematical model data they are derived from that often have large margins of error ie best taken with a healthy dose of pragmatism.

Pragmatism in this case will result in my best endeavours at a 2 litre starter then in it goes! Cheers for the more scientific outlook though

 

[SMP Brewery]

I have a question about starters which I guess can fit in here.....

If I dont have the needful to fit a 2 litre starter in (I dont have a decent flask that size) Do I get the same cell growth from pitching the yeast into a 1 litre started, letting it ferment out, then pitching the settled yeast into another 1 litre starter?

I've just done this for the first time for the Rye IPA swap.. Brewfather suggested a 2.7 ltr Starter my flask is 2 ltrs so after splitting it into 2 it cam back with.

 

[dmtaylor]

Skip the calculators. If you use liquid yeast, use one pack and make a 1 or 2 litre starter, depending on whether it's ale or lager. If you use dry yeast, sprinkle a pack on top and don't worry about it. Simple as that.

 

[AJA]

Skip the calculators. If you use liquid yeast, use one pack and make a 1 or 2 litre starter, depending on whether it's ale or lager. If you use dry yeast, sprinkle a pack on top and don't worry about it. Simple as that.

Sound advice, works for 90% of beers, unless you have a high gravity wort, or you are repitching yeast.

 

[aolcot]

Yeah I use brewfather and normally Lallemand yeasts and BF always seems to recommend far more than what Lallemand say they pitching rates should be for any given yeast. I've had recipes where BF says i need 3 or even 4 packets for a 22L batch!!
I now generally lean towards the manufacturers pitching rate and a little of my own experience rather than brewfather pitching rates. I did speak to a Lallemand representative at brewcon about the pitching rates I was using because of BF and he said that I was overpitching. I'm getting really good beers using the manufacturers pitching rates and saving me money as well as dried yeast isn't so cheap nowadays..

I do want to go back to liquid yeasts later this year to fine tune how many cells I build, plus I can overbuild and store some excess for a subsequent batch all of which will hopefully save those pennies in the long run

 

[DocAnna]

My approach is to keep the liquid I pour off from a starter in some Kilner jars to settle out for another week or so in the fridge then discard the clearer supernatant beer and store the residual yeast for the next beer. I'm getting a bit more organised about labelling them now as well. I do have a separation funnel but have rarely used it up till now. I'm going to have a go though with cleaning up the yeast cake from a lager I'm making at the moment to see how well that works.

 

[Brewnaldo]

I think the yeast manufacturers are a wee bit culpable for the confusion here tbh. Almost every yeast pack you ever see, dry or liquid (and I concede there's not room on them for loads of info) would have you believe that for a 23 litre batch of whatever you are brewing, you are pretty much good to go. Dig a little deeper even on the same manufacturers websites and you will find that actually, you should be doing a bit of further work.

 

[AJA]

Yeah I use brewfather and normally Lallemand yeasts and BF always seems to recommend far more than what Lallemand say they pitching rates should be for any given yeast. I've had recipes where BF says i need 3 or even 4 packets for a 22L batch!!
I now generally lean towards the manufacturers pitching rate and a little of my own experience rather than brewfather pitching rates. I did speak to a Lallemand representative at brewcon about the pitching rates I was using because of BF and he said that I was overpitching. I'm getting really good beers using the manufacturers pitching rates and saving me money as well as dried yeast isn't so cheap nowadays..

I do want to go back to liquid yeasts later this year to fine tune how many cells I build, plus I can overbuild and store some excess for a subsequent batch all of which will hopefully save those pennies in the long run

You can harvest dry yeast you know! Exactly the same as liquid yeast after gen 1.