Problems Mr Malty Pitching Rate Calculator V5.02

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TBird

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I've just bought the Mr Malty pitching rate calculator for iPhone and can't get it to work.
I put in the following: Type AleOG 1.052Litres 23Manufacture date 6/12/2010 (it's an old yeast but has been stored properly)Intermittent shaking
It comes up with the following:
Viability % 1
Yeast cells needed 221 billion
Vials / Packs without starter: 221.0
Starter: 74.0 packs in 2.04 litres
Obviously something is way out of whack.
I can't get the contact details from the website ( when you hit contact, it comes up with "Not Found" error).
Can someone who has a working version of this run those figures through it and see if I'm doing something wrong.
Thanks
 
2010?!

1% is probably as low as the calculator goes. Could be completely dead.
 
Did you correctly select the dry/liquid yeast option?

Your viability is way down, if you chose liquid yeast and it the manufacturing date is 2 years ago that is probably where your problem is. :icon_cheers:
 
It seems that Mr malty defaults to 1% for anything more than just over a year old.

Put in 19/12/11 and it shows 1% change the date to 20/12/11 and it goes up to 10%
 
I got a bit confused using the online version.

About 6 months ago I bought a pack of Wyeast 2001 to make a Pilsner. Up to that point I'd only used dry yeast. After researching if I needed to do anything special with a liquid yeast, I read that it was recommended you always make a starter. Having never done a starter, I got a bit spooked and just used S23 instead. The 2001 has sat in the fridge ever since.

I have since had a crack a re-culturing Coopers yeast from stubbies. It worked perfectly and I realised how easy making a starter was. So I gathered the ingredients for a Boh Pils and commenced making my starter. I used Mr Malty and it calculated a viability of 10% for my yeast and said I would need 12 packs for my starter :blink:
Is that right???

Anyway, after using the Wyeast pitching calculator, I decided to do a 1 litre starter then step it up to 2 litres. On Sunday I boiled up 100g LDME in a litre of water, cooled it then pitched the 2001. I don't have a stir plate, so it sits on the fridge and I give it a shake every time I go past (or SWMBO does while I'm at work, she's a good woman ;) ). It's not frothing on it's own yet, but lets out a hiss when you undo the cap so I think it's getting there (I've got it in a 2 litre juice bottle with the cap slightly looosened to let CO2 out, I just tighten it up to shake the bejesus out of it). Once it has frothed up I'll boil up another litre of wort to add to it and hope it's ready to pitch by the weekend.

Am I doing anything incorrectly? Will I be under-pitching or stressing the yeast at all?

Cheers,
 
Mr Malty seems to be pessimistic on old yeasts viability, and doesn't support multi-stepped starters

So its a great calculator if you're making single batches with fresh yeast.

For a multi-step calculator ccheck out http://www.yeastcalc.com

Pity it doesn't work on the iPhone :(
 
Just make a starter.

That's why I used the calculator - to determine the size of starter.
I can't see how a pack of yeast would have a viability of 1% two years after the manufacture date if it was stored in the fridge. I've smacked it last night and its now swollen so I'll give it a go with a two litre starter.
Thanks all for your input.
 

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