Rehydrate Dry yeast then put on stir plate?

[Mirilis]

So I have only 1 packet of dry lager yeast for a munich dunkel I intend to make next week. What I would like to do is make a ~1.25L starter wort, then rehydrating the dry yeast and pitching it to the starter and setting it on my stir plate until it ferments out. Then putting it in the fridge the day before I pitch to the lager.

Anyone got a better method? The yeast calc never assumes you will hydrate dry yeast and make a starter.

 

[douglasbarbin]

A better method would probably be to just pitch 2 packs of dry yeast.

 

[passedpawn]

That sounds ideal to me. 1.25 isn't a very big starter though, not sure you're going to get a lot more yeast growth from that. According to the yeast companies, rehydration can produce double the number of viable cells.

Someone always comes into these threads and correctly reports that those same yeast companies recommend just tearing and pitching directly into the wort. That does work of course, but it's not ideal, expecially for a lager. Why do they recommend it then? Probably, because it's a LOT easier than making a starter, and also any handling of the yeast once the packet is opened invites infection. Imagine if they had to put starter instructions and sanitation advice on that little packet? And when the beer tastes like ass, who do you think takes the heat

 

[passedpawn]

A better method would probably be to just pitch 2 packs of dry yeast.

I do agree with this. I'd still rehydrate though. OP must have a reason for not getting more yeast.

 

[Mirilis]

I only have one packet, and I am not able to acquire another since my LHBS does not carry Mangrove Jack. I need ~385 B cells

and I always rehydrate. If you buy 500g bricks with a wholesale license, that is how the mfg recommends you use the yeast.

MrMalty calculator says if i use 2 liquid packages (~200 B cells) then I need a 1.54 L starter on a stir plate. Mangrove Jack sachets are 10g and if you assume 20 B cells per gram then there are ~200 B cells in the 1 sachet. So it would be basically the same thing then if I rehydrate and pitch to my 1.54 starter..

at least thats my logic.

 

[flars]

Try this calculator. BU doesn't ask if the yeast is dry or wet. Just enter the estimated cell count for Mangrove Jack yeast when it is rehydrated and go from there.
http://www.brewunited.com/yeast_calculator.php