# How can a Smack pack not even be good for only 3.5L of wort!



## Mozz (18/9/16)

WTF?


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## Mozz (18/9/16)

I want enough for a 42L lager brew.
I can step it up in 2L then 4L (stir plate). Was hoping to get there in one step but doesn't seem possible?


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## Lyrebird_Cycles (18/9/16)

Wyeast predicate their offering on a pitch rate of 5.5 x 106 cells/ ml for standard ales and double that for lagers and high gravity brews (two packs).

You have set your required rate at almost 20 x 106 and discounted the available cells by ~40% due to the age of the pack. Something's gotta give.


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## Danscraftbeer (18/9/16)

No way enough yeast in one step unless you have one big flask.

You start with 62 billion cells and you need around 750 billion cells. There's a few step ups needed and best practice is essential on all steps etc. 

For example I use 3 packets of w-34/70 and step that up in a 2.6lt/1.040 on stir plate. Take that settled yeast cake for a 40lt lager brew at 1.050. By my calcs that was slightly under pitched. But it brewed well.
Given that dry yeast packs are double the yeast count of liquid yeasts I think in general? Sounds like you would need around 6 packs stepped up once to get you into the ball park? 
That's loose calcs trying to keep it at layman's terms as I am. 


Sorry if that's confusing. Edited to try clarify.


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## Cosh (19/9/16)

You're trying to ferment out 45 L of lager with one smack pack at 60% viability?

As suggested above, you'll need at least two starter steps to get to the required pitch rate. Pitch the smack pack into a 2.0 l starter and step up to a 5.0 l one. 

That should give you the 750 billion you need.


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## Mozz (19/9/16)

I knew I'd need to step up but assumed it would be a single step. 
Just wanted to confirm that everyone is indeed doing big starters and I presume then dumping all that supernatant! 
Ouch when it 6L or so but hey if that's what one must do.
Lyrebird I'm just using the yeast calc defaults. Just really surprised a pack could only theoretically adequately pitch 3L based on that. What you say brings a pack close to the 20L (10L for lager) mark. 
Why does Wyeast suggest an adequate pitch 4x (2x for lager) less than the yeast calcs? How could this be? A starter would surely contain more vigorous yeast than a package kept in storage for a month or so. (Don't have the luxury of picking up from the Wyeast factory on package day)
Are the yeast calcs over conservative?.
I've been making starters for my ales with great improvement, (not going back to just pitching dry yeast), but the amounts required for a lager are a new ball game.


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## Danscraftbeer (19/9/16)

This is the appeal of recycling/harvesting from your yeast cakes etc. Its a worthy brewing skill. I just put down a 40lt lager at 1.060 with harvested yeast that's equivalent to maybe $40 worth of yeast. No starter necessary. Scoop some of the yeast cake after racking the last brew and keep in mason jar in fridge until you pitch into the next brew. That's usually the same day for me.
I don't like wasting malt in starters either.


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## jbaker9 (19/9/16)

+1 for recycling. I have 2 large beakers that I use for starters. I just boil water in both of them with foil caps to sanitise then let them cool. A little bit of the water goes into yeast cake, then shake and drain the lot into 1 beaker. Leave for trub to settle and pour into 2nd beaker. Chill overnight for yeast to drop from suspension. Like danscraftbeer I like to do this just the day before my brew.

There are plenty of yeast calculators to determine how much you should use.

It sounds like a lot of work but really isn't. Just a matter of being organised. With practice it will become part of your brew routine. For high OG beers it is normal practice to brew low OG beer first and use complete yeast cake.


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## Mozz (19/9/16)

So I'm kegging an Ale tomorrow. 
I cold crashed on the 16th. 
Have just made a wort and will pitch some slurry as suggested.
Regardless I'll need to make stepped starters for the lager I want to brew next.
My question now however is how long can you store a slurry at 1C and still be good for repitching? I doubt I will always be in a position to repitch the day after kegging.


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## goatchop41 (19/9/16)

*Flame suit on*

Take what you will from these. A lot of people rubbish these guys' methods, but I think that it should lead to some valid discussion about reusing slurry (up to 14 weeks old!), with or without a starter:

http://brulosophy.com/2015/03/02/sloppy-slurry-vs-clean-starter-exbeeriment-results/

http://brulosophy.com/2015/07/15/sloppy-old-slurry-starter-vs-fresh-yeast-exbeeriment-results/

http://brulosophy.com/2015/08/24/sloppy-old-slurry-no-starter-vs-fresh-yeast-exbeeriment-results/


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## Mozz (19/9/16)

Found my answer I think. 
Sounds like it's good for some time.

http://aussiehomebrewer.com/topic/41324-how-long-can-you-keep-and-re-use-yaest-slurry/


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## Mozz (19/9/16)

Haha Goatchop. Simultaneous. Came to the same answer from an AHB post from 2010. Sounds like it can be good for months. Cheers.


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## black_labb (29/9/16)

You can always use the starter wort as part of the brew if you dont oxygenate for too long and keep the steps and temp ok to avoid undesireable flavours. If you no chill then you can add the second cube a couple days after the first is pitched making your actual brew part of the yeast step ups.


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