Mr Malty calculator and half packs of dry yeast

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BrewDaddy

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Hello - I'm curious to know whether there is a consensus on what to when do when the recommended quantity of dry yeast to use isn't a whole number.

For example, a 23 litre batch @ 1.059 @ 80% visibility - the Mr Malty calculator recommends 1.4 packs,

Am I best to round up and use 2 packs, round down and only use 1, or actually take the time to measure out .4 of a pack??

What is worse, over or under pitching???
 

mje1980

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Use 2 packs. What would you do with the half a pack you don't pitch?, probably wouldn't be sanitary to keep it, so just throw it in. Won't hurt
 

Yob

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Underpitching is worse, you get less ester development from an over pitch but is preferable to stressed under pitched yeast.. Clearly a 'correct' rate is best but if it has to be a direction, over not under.
 

felten

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Do a partigyle or something that will take half a packet :)
 

Danielscott26

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What is the recommended amount when doing a 12 litre batch? Im currently brewing 12 litre batches and dont really want to try to store half packets of yeast.
 

Yob

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Personally, I'd be going with slurry if I could, much easier to tailor the pitch rate.
 

Nick JD

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I've found with big, hoppy American Ales I can be pretty lax about pitching rates - a bit under and you'll get esters which no one will ever be able to taste over the 2g/L dry hopped Citra - a bit over is also no problem.

Also been running IPAs in the mid 20s lately with zero issues ... the whole "18C" for ales when they have a metric shitload of hops in them is a bit tedious IMO.

I get really very anal when pitching yeast into lagers though.
 

hellbent

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Nick JD said:
I get really very anal when pitching yeast into lagers though.
Anal pitching yeast??..... The mind Boggles! :huh:
 

slash22000

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I made a thread about this somewhat recently. Give it a read.

Also, I seriously doubt your yeast is only 80% viable. Dry yeast loses ~4% viability every 12 months in the fridge, ~20% viability every 12 months at room temperature. So unless your yeast is 5 years old, or it's been kept outside the fridge all year, I'd work off at least 90% viability.
 

BrewDaddy

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slash22000 said:
I made a thread about this somewhat recently. Give it a read.

Also, I seriously doubt your yeast is only 80% viable. Dry yeast loses ~4% viability every 12 months in the fridge, ~20% viability every 12 months at room temperature. So unless your yeast is 5 years old, or it's been kept outside the fridge all year, I'd work off at least 90% viability.
So what did you end up doing and how did it turn out??

I want to keep things as cheap / basic as possible. I like the idea of just sprinkling 1 pack directly into the wort. I pretty much exclusively brew 23 litres up to a max of 1.060 (ad usually and 1.050) - always figured that 1 pack was sufficient.

I've also read about if you don't re-hydrate you'll lose half the yeast right away, and that re-hydration is a simple step. It looks me like another place where I run the risk of screwing something up.
 

slash22000

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I haven't actually made that particular beer yet. I had intended to make it by now, but have been distracted.

If you think rehydrating yeast is beyond your abilities then you might want to sign yourself up for one of those "You are capable!" motivational speeches. :lol: If you can walk in a straight line, you can rehydrate yeast.
 

BrewDaddy

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slash22000 said:
I haven't actually made that particular beer yet. I had intended to make it by now, but have been distracted.

If you think rehydrating yeast is beyond your abilities then you might want to sign yourself up for one of those "You are capable!" motivational speeches. :lol: If you can walk in a straight line, you can rehydrate yeast.
you're right - boil water, let it cool, add yeast, wait, add to fermenter.....maybe time for me to man up.
 

Pickaxe

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My guess is that anal pitching yeast would go best at body temperature? 36-37 degrees?
 

carniebrew

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BrewDaddy said:
Hello - I'm curious to know whether there is a consensus on what to when do when the recommended quantity of dry yeast to use isn't a whole number.

For example, a 23 litre batch @ 1.059 @ 80% visibility - the Mr Malty calculator recommends 1.4 packs,

Am I best to round up and use 2 packs, round down and only use 1, or actually take the time to measure out .4 of a pack??
Have you given any thought to reducing the batch size to whatever you'd need to just pitch 1 pack?
 

BrewDaddy

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carniebrew said:
Have you given any thought to reducing the batch size to whatever you'd need to just pitch 1 pack?
Reducing batch size??? I cannot comprehend this logic :D
 

felten

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Well you could always do a double batch instead :D
 

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