How much yeast?

[Danny's Juice]

This has probably been asked many times, how much yeast is meant to go into the FV? I've just been using the yeast from the Coopers cans which is 7g I think, but is there a limit on how much yeast should be put in and what are the results for too much or too little?

[ben 10]

Martin has written a very useful document here which goes to great lengths to discuss the pros and cons of too little / too much yeast.

Mr Malty has a calculator for yeast pitching rates too.

The aftermarket yeasts tend to be in the order of 11g...

[JohnE9]

Thanks very much Ben for posting those two very, very useful links on yeasts and their pitching rates.

 

Most informative.[happy]

[CanaKiwi]

Hey guys,

 

I just put down this partial mash,

 

Cooper's Light LME - 1.5 kg

Light DME - 0.500 kg

Grain - Pale Malt - 1.3 kg

Grain - Chocolate Malt - 0.300 kg

Grain - CaraPils Malt - 0.120 kg

Grain - Crystal Malt 60 - 0.120 kg

Brown Sugar - 0.150 kg

Hops - Northern Brewer - 18 g @ 60

Hops - Cascade - 7 g @ 5

Vanilla Beans - 2 (will go in secondary)

Yeast US-05

 

Ian H's spreadsheet estimated an OG of 1.045-1.050 and I ended up with an OG of 1.053.

Mr.Malty says I should add 12 g of yeast, and I'm debated on whether or not to just let it go with the 11g I already put in, or if I should open op my extra packet of US-05 and pitch it in too.

 

What do you think?

[Hairy]

Just stick with the 11g you have already pitched. I wouldn't use up an extra packet of US-05 for the sake of 1g of yeast.

 

It isn't a precise measurement anyway as you don't know how much viable yeast you have in a packet.

[Beerlust]

Hi CanaKiwi.

 

You are certainly right around the gravity limit for a single pack of yeast. The US-05 is particularly aggressive & vigorous from my regular uses with it. I'd use just the one packet, & monitor your gravity readings against what is expected for that brew.

 

What temperature do you plan to ferment the brew at? Allowing it to slip into the low 20's will certainly be beneficial given your concerns in this area.

 

Just my 2 cents.

 

Cheers & good luck with the brew,

 

Anthony.

[CanaKiwi]

Thanks for the reassurance Hairy and Anthony. It felt wasteful to use the second pack of yeast but I had read before that around 1.05 was the top end for a single package of yeast. I'll just monitor things for now.

 

I am currently fermenting at 18°C in my brew fridge. Anthony, did you mean you think I should let it go in the low 20s for the whole fermentation or to let it rise in a few days?