Splitting A Wyeast Smack Pack

[Fourstar]

A good point. I have made 100g/1L wort for a starter and and ended up with wort of G 1.050 after a 10 min boil on the cooktop, not a raging boil, just a low boil, a trap for new players. Check the gravity of your starter wort!!!
Screwy

Yes, sorry for the new players. I thaught it was self explanetory, you assume you amke an arse of yourself! :icon_cheers:

100g/1L should be your post boil volume. Not your starting boil volume. So if your are boil for 15-20 mins, maybe start it at 1200ml and boil down to 1L.

 

[Nick JD]

...after that time the yeast viability drops drastically and you'll need to make a starter anyway.

Why does this happen? I haven't found this to be the case.

 

[cubbie]

Tony a great post. I normally make one starter from a smack pack pitch most and then fill 2 x 30ml test tubes (same as you use). I like the thought process behind your method and I will try this next time.

A few questions.

a. What do you calculate as the number of yeast cells left in the smack pack and in each test tube
b. What is your method to build your yeast numbers up to your required pitching rate - I would expect that simply adding the remaining yeast in a Smack Pack or yeast in a 30ml test tube to not be enough
c. If you are using Mr Malty how do you plug these details in.

Cheers.

 

[lock]

I boil mine down until reaching a gravity around 1.035 - 1.040. Boil time depends on the gravity of the runnings from the mash tun and can vary.

Wouldn't it be easier to make sure your original wort sample is close to 1.030 and then boil that down?

Great post Tony. I've been thinking about something like this for a while and you've given me the knowledge to have a crack at it.

 

[Screwtop]

Wouldn't it be easier to make sure your original wort sample is close to 1.030 and then boil that down?

Great post Tony. I've been thinking about something like this for a while and you've given me the knowledge to have a crack at it.

**** yeah it would! Do it whatever way you prefer............but, ever tried doing it?

I boil the wort for 5 minutes and take a sample for the refrac and then again at 10 min, the same as I do when boiling in the kettle, take a gravity reading after 60 min to get an idea of how my boiloff rate is going, then again at 30 min (90 min boil). Each boil is different, given ambient variables, taking a reading at 30 min then calculating the boiloff allows the brewer to adjust the burner of volumes to better hit target OG at the end of the boil. I normally boiloff 5+L per hr but the batch I made last week was at 8L/hr at 30min so added some boiled water to compensate at 30 min. It's very difficult to judge by observing the boil if it is boiling at your "normal boil rate", wind, temp etc effect boiloff volume.

Cheers,

Screwy

 

[Thommo]

Top post Tony.

Went out and bought some sample jars from the chemist so I can start doing this on the weekend.

Thanks for the great info.

Thommo.

 

[AndrewQLD]

**** yeah it would! Do it whatever way you prefer............but, ever tried doing it?

I boil the wort for 5 minutes and take a sample for the refrac and then again at 10 min, the same as I do when boiling in the kettle, take a gravity reading after 60 min to get an idea of how my boiloff rate is going, then again at 30 min (90 min boil). Each boil is different, given ambient variables, taking a reading at 30 min then calculating the boiloff allows the brewer to adjust the burner of volumes to better hit target OG at the end of the boil. I normally boiloff 5+L per hr but the batch I made last week was at 8L/hr at 30min so added some boiled water to compensate at 30 min. It's very difficult to judge by observing the boil if it is boiling at your "normal boil rate", wind, temp etc effect boiloff volume.

Cheers,

Screwy

I think Lock has the easier method,

Wouldn't it be easier to make sure your original wort sample is close to 1.030 and then boil that down?

I use an Erlenmeyer (sp) flask to boil my starters, it's marked in volume measurements. 220g of dry malt extract goes into the flask and it's topped up with water to the 2.45l mark O.G 1.033, it's then put on the stove and boiled until the volume drops to the 2lt mark, that brings the O.G up to 1.040.
You can adjust malt and water quantities for whatever O.G you require, I just put the figures into beersmith when I am too lazy to work it out myself.

Edit: Mind you this method assumes you have a reasonably accurate way to measure your wort volume.

Andrew

 

[Wolfy]

Why does this happen? I haven't found this to be the case.

Because yeast dies over time, it's why smack packs/vials/dry yeast all have use-by dates.
It's why everyone suggests that older smack-packs take longer to swell than newer ones - often taking more than a few days, depending on their age - a bunch of the yeast has died so it takes the remaining yeast more time to propagate and eat through the food in the smack-pack.
It's why when using the MrMalty calculator you get such different results if you adjust the 'production date' setting.
Sure, cup of saved/washed yeast slurry will have enough viable cells to directly pitch if it's a week or few old, however if it's been saved for 6 months to a year, I doubt any resonable person would expect to pitch it directly without a starter.

 

[Tony]

So you fill up plastic test tubes with the smack pack?

Yep

Tony a great post. I normally make one starter from a smack pack pitch most and then fill 2 x 30ml test tubes (same as you use). I like the thought process behind your method and I will try this next time.

A few questions.

a. What do you calculate as the number of yeast cells left in the smack pack and in each test tube
b. What is your method to build your yeast numbers up to your required pitching rate - I would expect that simply adding the remaining yeast in a Smack Pack or yeast in a 30ml test tube to not be enough
c. If you are using Mr Malty how do you plug these details in.

Cheers.

a. pack says 100 million so i guess about 25 Million in each vial and 25 million in the starter. Once the starter is done there is far more yeast than you would get from a single smack pack. I pitch this strait into 50 liters and works great! For lager yeasts i will usually step up a second time (Oh that sounded very Monty Python)
b. I make a starter for each vial before i use it. I make 50 liter batches so only brew monthly...... its not an issue for me.
c. Never heard of it!

Because yeast dies over time, it's why smack packs/vials/dry yeast all have use-by dates.
It's why everyone suggests that older smack-packs take longer to swell than newer ones - often taking more than a few days, depending on their age - a bunch of the yeast has died so it takes the remaining yeast more time to propagate and eat through the food in the smack-pack.
It's why when using the MrMalty calculator you get such different results if you adjust the 'production date' setting.
Sure, cup of saved/washed yeast slurry will have enough viable cells to directly pitch if it's a week or few old, however if it's been saved for 6 months to a year, I doubt any resonable person would expect to pitch it directly without a starter.

smack bang on the money Wolfy!.

For the record..... I have had massive problems since i moved into my current house with odd bugs that grow on the top of the brew. the first brew is usually ok but if i reuse the yeast (which i did a lot at my last house with no problems) the next brew will get a white skin on it and tastes funky. Its a wild yeast issue in the air and very hard to stop. Soooooooo i only ever use virgin yeast.... hence my method.
Lots of methods work well...... I thought i would just show my method that works for me.

cheers

 

[davewaldo]

a. pack says 100 million so i guess about 25 Million in each vial and 25 million in the starter. Once the starter is done there is far more yeast than you would get from a single smack pack. I pitch this strait into 50 liters and works great! For lager yeasts i will usually step up a second time (Oh that sounded very Monty Python)
b. I make a starter for each vial before i use it. I make 50 liter batches so only brew monthly...... its not an issue for me.
c. Never heard of it!

Thanks for the info Tony. So just to clarify (I'm new to starters), You take a 25 million cell sample and make a 2L starter and you find this is enough for a 50L batch of normal gravity ale? And double that for a Lager?

Cheers,

Dave.

 

[Nick JD]

Because yeast dies over time, it's why smack packs/vials/dry yeast all have use-by dates.
It's why everyone suggests that older smack-packs take longer to swell than newer ones - often taking more than a few days, depending on their age - a bunch of the yeast has died so it takes the remaining yeast more time to propagate and eat through the food in the smack-pack.
It's why when using the MrMalty calculator you get such different results if you adjust the 'production date' setting.
Sure, cup of saved/washed yeast slurry will have enough viable cells to directly pitch if it's a week or few old, however if it's been saved for 6 months to a year, I doubt any resonable person would expect to pitch it directly without a starter.

I wonder what the mortality rate of yeast is kept at 4C in beer? Anyone know?

 

[Wolfy]

I wonder what the mortality rate of yeast is kept at 4C in beer? Anyone know?

The pitching rate calculations in MrMalty are based on information I've read in several books, but I'm not sure where the viability V's harvest date calculations come from.
However, assuming that it's based on valid information, it does indicate a viability of 50% after only 1 month of storing yeast slurry, and 10% after 6 months storage.
So if those numbers are even close to being correct, if you store your slurry for more than a few weeks, creating a starter before re-pitching saved slurry appears to be a 'must' - which I think most resonable brewers would agree with, especially to test and check the viability, activity and the health of the yeast before pitching.

 

[Nick JD]

The pitching rate calculations in MrMalty are based on information I've read in several books, but I'm not sure where the viability V's harvest date calculations come from.
However, assuming that it's based on valid information, it does indicate a viability of 50% after only 1 month of storing yeast slurry, and 10% after 6 months storage.
So if those numbers are even close to being correct, if you store your slurry for more than a few weeks, creating a starter before re-pitching saved slurry appears to be a 'must' - which I think most resonable brewers would agree with, especially to test and check the viability, activity and the health of the yeast before pitching.

Thanks, Wolfy - where would I find some viability information? 50% after one month seems to be in line with my experience - if you can count noticing lag time variations. That said I regularly pitch months-old trub and have active fermentation within 5 hours, so I'm guessing the pitching rate is okay - and I might be over-pitching younger yeast.

A fella on another thread just told us 72 hours is as long as it'll keep.

I'd like to use Tony's method but I can't be assed making starters for every brew - I only do small batches (~15L) and it just doesn't make sense for me. But I fully appreciate the need for a starter in a 60L lager; my 15L brews would be perfect as 60L starters.

 

[Tony]

Thanks for the info Tony. So just to clarify (I'm new to starters), You take a 25 million cell sample and make a 2L starter and you find this is enough for a 50L batch of normal gravity ale? And double that for a Lager?

Cheers,

Dave.

Yep

I'd like to use Tony's method but I can't be assed making starters for every brew - I only do small batches (~15L) and it just doesn't make sense for me. But I fully appreciate the need for a starter in a 60L lager; my 15L brews would be perfect as 60L starters.

I wouldnt make a starter for a 15 liter batch either. even after a month in the fridge and 50% loss...... a good dose of healthy yeast from a previous batch will kick it in. I have done it many times. Every now and then i got one that didnt fire though, and lost the batch as a result so i started making starters to prove the yeast. 10 to 12kg of grain, a days work and up to 1/4kg of hops is too much to risk to saving $2 on yeast!

 

[cubbie]

Yep




a. pack says 100 million so i guess about 25 Million in each vial and 25 million in the starter. Once the starter is done there is far more yeast than you would get from a single smack pack. I pitch this strait into 50 liters and works great! For lager yeasts i will usually step up a second time (Oh that sounded very Monty Python)
b. I make a starter for each vial before i use it. I make 50 liter batches so only brew monthly...... its not an issue for me.
c. Never heard of it!




cheers

Tony I was reading How to Brew last night and there is a great table in the Yeast section which gives a guide to how much yeast you will get from a certain starting cell count and x volume of starter. The first row in the table suits your method very well. From memory it was something like 30 billion cells (the packs has billions not millions) in a one litre starter produces about 90 odd billion cells, in a 2L starter it is about 115 billion. If you put your 90 billion from the one litre starter into a 2L starter it produces about 215 billion cells. These figures are from memory. I had a look at the online version of How to Brew but could not find the table.

This table along with the formula below I find a lot simpler to use than the Mr Malty calculator (which you have never heard of)...


http://www.mrmalty.com/pitching.php
"If you're curious, here is the simple math to calculate the number of cells needed. For an ale, you want to pitch around 0.75 million cells of viable yeast (0.75 million for an ale, 1.5 million for a lager), for every milliliter of wort, for every degree plato.

(0.75 million) X (milliliters of wort) X (degrees Plato of the wort)"

 

[MattC]

a. pack says 100 million so i guess about 25 Million in each vial and 25 million in the starter. Once the starter is done there is far more yeast than you would get from a single smack pack. I pitch this strait into 50 liters and works great! For lager yeasts i will usually step up a second time (Oh that sounded very Monty Python)

So in theory what you are doing is creating 4 Propagator packs (minus the nutrient pack of course) from one Activator pack?

Sounds good to me

Cheers

 

[MattC]

OK, firstly i will apologise in advance for my lack of knowledge and urgency in this department but I am just beginning to use liquid yeasts, and I have run out of beer (except a double batch fermenting at present).

Im going camping tomorrow and will be back home thursday arvo. I am planning on doing MUST DO a brew on the following sunday and will be using a wyeast smack pack 1275. It will be a 44 L batch. After reading this thread I want to split the wyeast pack into 4 (store 3 and use 1 in a starter stepping up from 250 ml to 500 ml to 2 L over the 4 days from thurs to sunday (hopefully pitch late Sun night or Mon morning.

The production date on the wyeast pack is April 26 2010

I have been using the pitch rate calculator on the wyeast site

http://www.wyeastlab.com/hb_pitchrate.cfm

and Mr Malty

http://www.mrmalty.com/calc/calc.html

On the wyeast site it tells me I need about 6 million yeast cells per ml of beer (44 L and 1049 OG) which equates to about 264 billion cells required. When I punch in the numbers into the wyeast pitch rate calc it tells me that by using 0.25 of an activator pack and and a 0.5 gallon starter with a stir plate I will end up with 3.2 million cells / ml, about half what I need. If i use the whole activator pack I end up with about 7 million/ ml.

Using the Mr malty calc I punch in the date it tells me my yeast is about 45% viable. I put in the rest of the numbers and it comes out telling me that I need 3 packs or vials and a starter of 2.3 L.

I have a few questions

1. Is the final cell count for a 2 L starter more when you use more of smack pack to start? I was assuming that the end result would be the same but it would take less time with more of the smack pack used??

2. Approx how long would it take to step up to a 2 L starter and have it finished with using 1/4 of a smack pack? (Im contemplating taking the smack pack to my parents and giving dad instructions to activate it on Tuesday on my behalf) - I can here him now, "what do you worry about this s@#t for, I never worry about this when I brew" (K & K man my dad).

3. Am I on the right track with this? if not could you please redirect me,


Thanks in advance for any advice :icon_chickcheers:

 

[Wolfy]

3. Am I on the right track with this? if not could you please redirect me,

The MrMalty calculator is designed for pitching the pack directly into the stater size it recommends. By stepping up the starter a few times, you are taking a different approach, but IMHO it's accurate enough to still be appropraite. By taking several steps while making the starter I think it's fair enough to assume that you'll end up with much the same amount of viable yeast when you reach the starter volume as per what the calculator suggests.

Personally, I'd suggest a 100ml starter, stepped to 400m and then 2L (step sizes of between 4-10x are usually recommended). Given its a new pack of yeast, you might expect it to fire-up quickly, but I'd suggest at least 1 day for each step and then one day extra to let it flocculate/settle out before you pitch it (the extra day is also good in-case it takes longer).

Other than that, pretty much sounds like the right way to go to me.

 

[MattC]

The MrMalty calculator is designed for pitching the pack directly into the stater size it recommends. By stepping up the starter a few times, you are taking a different approach, but IMHO it's accurate enough to still be appropraite. By taking several steps while making the starter I think it's fair enough to assume that you'll end up with much the same amount of viable yeast when you reach the starter volume as per what the calculator suggests.

Personally, I'd suggest a 100ml starter, stepped to 400m and then 2L (step sizes of between 4-10x are usually recommended). Given its a new pack of yeast, you might expect it to fire-up quickly, but I'd suggest at least 1 day for each step and then one day extra to let it flocculate/settle out before you pitch it (the extra day is also good in-case it takes longer).

Other than that, pretty much sounds like the right way to go to me.

Cheers wolfy, anything wrong with refrigerating the starter overnight to speed up flocculation, i did that last time with a 2 L starter (after checking SG to make sure it had fermented out) and it took off in about 8 hours in 44 L batch.

One other question, do you step up to the next starter when the previous is at high krausen?

 

[Wolfy]

Cheers wolfy, anything wrong with refrigerating the starter overnight to speed up flocculation, i did that last time with a 2 L starter (after checking SG to make sure it had fermented out) and it took off in about 8 hours in 44 L batch.

One other question, do you step up to the next starter when the previous is at high krausen?

It's not uncommon to put the starter in the fridge overnight to help the yeast settle, however if you can let it ferment out first.
I think it's 'best practice' to step up at high krausen, however - for a starter - that can be as quick as 12 hours (depends on the yeast of course), so I tend to do it when it's continent/easy for me and that usually means after about 24h.