Yeast Query

[cdbrown]

I plan on brewing a pilsner double batch soon. I have a packet of wyeast czech pils which I bought about 2 years ago. Going by beersmith the packet has about 5% viability so I'm trying to plan ahead. Beersmith also say I need to have about 727.3B yeast cells for the brew. When I create a starter in there it comes no where near enough. Using mr malty I need a 19L starter.

If I stepped up the starter from 200ml, then 500ml, 1L then 2L will that promote more healthy yeast cells than a 2L starter straight out? Am I going to be able to create a starter with the right amount of cells?

0.2L creates 27B yeast cells with a stir plate. Can I use that figure as the cell count for the viable cells when stepping up to 500ml? So I make the starter size in beersmith 300ml (that's all I've added to get to 500ml) that will give me 113B. Do the same again and change the starter to 500ml to reflect the then step up to 1L to give 303B, if I add another 500ml I'll get 812B which is just a bit more than I need.

I've never done stepped starters before and perhaps that's the reason why my use of liquid yeast has been hit and miss as the yeast has been too stressed due to low viability?

What do others do?

 

[Wolfy]

Yes a stepped starter will give you better/healthier yeast than pitching such a small number of viable cells directly into a 2L starter - so if your pack is old and/or you suspect the viability is low, stepping up the starters is a very good idea. However, step size of between about 4 and 10x is what is usually 'recommended'.

An easy (and over-simplified) way to estimate the number of cells in a starter is to assume that they will reach a maximum density of 100million cells per ml (= 100 Billion per L).
Which means to get 700 billon cells your starter will need to be 7L and not 2L - so you do: 200ml, 1L, 4L, split into 2x 4L to give you the starter size required.
(I use 4L starters for single lager batches - slant, 10ml, 50ml, 250ml, 1L, 4L).

However you also might find it just as easy to brew a single batch beer to build up enough yeast for your double batch.

 

[cdbrown]

7L - crap. I guess I could do a single batch with a 2L starter (flask is only 2L) and then take a few cups of the slurry at the end for use of the double batch. This is why I stuck with dry yeast - 4 rehydrated packets of swiss lager and it was ready to roll.

Palmer talks of chilling the starter over night and then pour off the beer at the top leaving the slurry and a few L of beer. This has to be better than pouring in 7L of fermenting 1.040 wort into a 42L wort?

 

[Thirsty Boy]

I say - put the 2yo wyeast in the bin where it belongs, and buy 3 or 4 packs of dried yeast for this batch.

Otherwise, tip that pack into 250ml of starter wort, step up to 1L, then 4L and split for a total of 7 or 8L - just as wolfy said (all assuming you have a stirplate) If you cant do that.... Then i think you will get a better result with dried yeast than with liquid yeast.

Its 4L per single batch... Not per double batch.

It all depends - do you actually want to use the proper pitching rates? If so, then its big flasks and a decent time commitment for lagers, especially double batches. If you are willing to compromise.... Then you might as well just compromise in the way that makes life easiest for you.

 

[yardy]

if it were me I'd brew a smallish session (starter) beer at 1.030 and harvest a decent slurry, no expert though.

 

[cdbrown]

I'll try and get the wyeast going and build up a starter. Will brew a single batch pils and get that fermenting with the starter. At the end I'll brew a double pils with different hops and use a few cups of the slurry. Cheers for the replies.

 

[CosmicBertie]

I'll try and get the wyeast going and build up a starter. Will brew a single batch pils and get that fermenting with the starter. At the end I'll brew a double pils with different hops and use a few cups of the slurry. Cheers for the replies.

I recently made my very first starter from some saved sludge out of the bottom of my fermenter. There wasnt much, I had to claim it from a lot of hot break (dont ask). Anyway, i used 50g LDME/500ml...after that had fermented out, i went upto 100g/1.0l. Once that had done, I put it in a jar with some cooled, boiled water, and stuck it in the fridge. When I was about to brew, i grabbed it out of the fridge, and put it in a warm place till room temp. Then, i created a 2L starter (200g/2000ml) and chucked it in just before I started to brew....crikey, it was at full kreysen (frothing!), by the time the wort was ready for pitching, and i just whacked the whole lot in. I reckon with that, it'll have fermented out within about 5 days!

The initial cultivation of the small amount of yeast took about 2 weeks as I got more hot-break than yeast in the jar

 

[mckenry]

Necro alert!

Not precicely to do with this thread, but couldnt find any answer to something I was pondering last night.

Lets say I stepped up a starter, for ease of numbers, from 1L to 2L to 3L.

Is that a 3L starter or a 6L starter?

Reason I ask, is I have many flasks, from 250mL through to 5L.

I often start at 0.4L then 1L then 2.3L and each time I just keep putting the entire last flask into the next size up, until my 5L (in this example) is 3.7L full.
I just wonder if I'd tell someone I just did a 3.7L starter, (as thats the total I have at the ensd) or a 2.3L starter as that was the last step up?
If I poured off the liquid each time, it would appear to be a 2.3L starter - but is it?

 

[mckenry]

Just a bumpity bump for the night crowd. What is the definition of a starter as per my q in prev post?

 

[mckenry]

Necro alert!

Not precicely to do with this thread, but couldnt find any answer to something I was pondering last night.

Lets say I stepped up a starter, for ease of numbers, from 1L to 2L to 3L.

Is that a 3L starter or a 6L starter?

Reason I ask, is I have many flasks, from 250mL through to 5L.

I often start at 0.4L then 1L then 2.3L and each time I just keep putting the entire last flask into the next size up, until my 5L (in this example) is 3.7L full.
I just wonder if I'd tell someone I just did a 3.7L starter, (as thats the total I have at the ensd) or a 2.3L starter as that was the last step up?
If I poured off the liquid each time, it would appear to be a 2.3L starter - but is it?

Hey Guys,
I'm still wondering about this :unsure:

 

[Helles]

3.7 lt