Can I pitch dry yeast + harvested slurry into a batch of beer?!

[Jayhem]

Odd question.

Here's the deal.

1. I want to brew tonight but I don't have time to make a starter for my washed (2nd generation) US-05 yeast.

2. I am making a 5.5 gal batch of IPA (OG: 1.060).

3. I have 1 packet of US-05 and about 1 cup of washed slurry that is about 2 months old.

Would it hurt anything to pitch the 2 month old slurry directly to my wort along with the 1 packet of the same yeast in dry form?

Yeast Calc says that I need 230 Billion yeast cells and I estimate that my washed yeast slurry has only 100 billion cells left as viable so I would need at least another 130 Billion cells.

I know that 1 packet of dry yeast is probably enough for a 1.060 5.5 gal wort but I would rather overpitch than underpitch an IPA. I'm just not sure if pitching dry yeast + slurry into one batch of beer would have any potential issues?

Thoughts?

 

[BBL_Brewer]

No, that won't hurt anything.

 

[tre9er]

Seconded. Yeast is yeast, be it slurry, dry, liquid vial, etc. It's all about cell counts and preparation of each type. Let the slurry warm up over the course of the brew day (decant beer from it, of course) and rehydrate the dry yeast. I think you'll be pretty darn close to the right counts, just a touch high.

 

[sweetcell]

one thing to keep in mind is that the packet is pure and clean, while the slurry invariably has some amount of bacteria in it. a pack has about 200B cells in it, so my plan of attack would be to go with the entire pack, and make up any difference with a bit of slurry.

if you have both a clean and dirty supply, max out the clean one first.

 

[tre9er]

one thing to keep in mind is that the packet is pure and clean, while the slurry invariably has some amount of bacteria in it. a pack has about 200B cells in it, so my plan of attack would be to go with the entire pack, and make up any difference with a bit of slurry.

if you have both a clean and dirty supply, max out the clean one first.

This makes some sense.

 

[Jayhem]

Thanks!