US-05 or WLP051 - Pitching rate

[Fallen]

I'm doing a Nelson Sauvin (dominated) brew this weekend. 40L batch, OG: 1.050.

Will a 2L starter from a single vial of WLP051 be enough to ferment out or should I use 2 packs of US-05 instead? I really want to try WLP051 in this one but I'm concerned about under-pitching. Mr Malty recommends 2 vials and a starter with 'occassional stirring'.

Cheers

[coatesg]

40L needs a little more than 2l I think. If you change the growth factor on the calculator, it should give you the starter size with one vial.

[Fallen]

Hmm, it's recommending a 3L starter with 2 vials of liquid yeast. I've only got one!

According to Mr Malty two 11.5g sachets of dry yeast would be OK. So, decision made, 2 sachets of US-05 it is.

WLP051 will be kept for another day!

[Wolfy]

Hmm, it's recommending a 3L starter with 2 vials of liquid yeast. I've only got one!!

Adjust the 'growth factor' slider and it will tell you how big a starter you need for one vial.

[Fallen]

Wolfy

I've adjusted the growth factor slider and its saying I need an 8.32L starter with one vial. This is a big percentage (~20%) of my final wort. I don't want to make 8.32L of starter in the way that I'm used to doing it (800g DME into 8L water) as this, IMHO, will adversely affect the final product.

So, how long does the starter need to grow i.e. can I add the WLP051 vial to 8L of the pre-boil wort that I'll be generating tomorrow (Sunday), incubate at ~20 degrees while the main boil/cooling is going on, then pitch when the wort is at the right temperature?

[coatesg]

You need about 24-36h to grow. To get round the large starter volume issue, grow the starter up and let it ferment out. Then stick it in the fridge, and let it settle out - after that you can decant the spent starter and pitch only the yeast. It helps if you have a stirplate as you can get away with a smaller size starter than occassionally shaking.

[Fallen]

Ah, common sense prevails! Cheers Graeme. I'll do this next time.

For tomorrow, US-05 is king.

[Wolfy]

I've adjusted the growth factor slider and its saying I need an 8.32L starter with one vial. This is a big percentage (~20%) of my final wort. I don't want to make 8.32L of starter in the way that I'm used to doing it (800g DME into 8L water) as this, IMHO, will adversely affect the final product.

So, how long does the starter need to grow i.e. can I add the WLP051 vial to 8L of the pre-boil wort that I'll be generating tomorrow (Sunday), incubate at ~20 degrees while the main boil/cooling is going on, then pitch when the wort is at the right temperature?

I totally agree with you, which is also why I use a stir-plate, check the numbers again and you'll see what a massive difference that would make.
My stir plate is nothing more than a speed-adjustable computer fan & 2nd hand 12V power adapter - dirt cheap and easy to make.

You should allow at least 24-36 hours for the majority of the yeast growth.
However, add another 12 hours to that to chill the starter so you can decant the spent starter-wort and pitch only the yeast.

[Fallen]

Cheers again Wolfy. Completely off the cuff, I decided on a different strategy altogether! See my partigyle post in brewdays.