What's the difference between dry and liquid yeasts?

[Oldpaddy]

I did my third all grain brew last night and I used dry yeast for the first time. I woke up this morning and the air lock was bubbling already. My two previous brews were with liquid yeast and they took longer to see action in the air lock. I find that odd.

Also, can I reuse dry yeast?

 

[cubalz]

Not odd at all. The main reason that happened is that typically dry yeast contains at least double the amount of cells that liquid contains (Imperial yeast is the exception)

Of course you can reuse your dry yeast, all yeast is the exact same once it is pitched.

 

[BrewnWKopperKat]

Also, can I reuse dry yeast?

It's probably a characteristic of each brand and/or strain of dry yeast.

If one chooses to read/follow information provided by the various yeast brands, Mangrove Jacks suggests this ...

As a result of the drying process, Mangrove Jack’s Craft Series dried yeasts are not suitable for harvesting and/or repitching. For best results, always use a fresh sachet of yeast with every brew.

(from the PDF downloat at: Craft Series Beer, Wine, Cider, Mead Yeast strain information).

Fermentis and Lallemand are likely to have different processes for making their brands of dry yeast and are likely to have different recommendations from Mangrove Jacks.

 

[Velnerj]

I'm prone to think that mangrove Jack's instructions are purely for marketing reasons. They know by reusing yeast they're losing profits. I've reused one or two mangrove Jack's before without issue.

 

[BrewnWKopperKat]

Homebrew Talk has a lot of strong opinions on MJ branded yeast. That's fine with me.

I've reused one or two mangrove Jack's before without issue.

Are you willing to mention the names of the MJ strains you have re-used?

 

[Vale71]

Fermentis and Lallemand are likely to have different processes for making their brands of dry yeast and are likely to have different recommendations from Mangrove Jacks.

So Mangrove Jack has found a way to insert a self-destruct in their dry yeast, you know, like when the tape goes up in smoke in Mission Impossible?
I'd like to see them try and justify such a ridiculous assertion.

 

[BrewnWKopperKat]

I'd like to see them try and justify such a ridiculous assertion.

They have a "contact us" page: Submit a request – Mangrove Jack's

 

[Velnerj]

Despite my anectodal claims which basically amount to nothing in the grand scheme of things. I just don't see the science here.

Even if the yeast was treated in some unique way to preserve its original state (highly unlikely) the yeast propagates itself so much into billions of daughter cells through the course of fermentation I can't fathom how that carries through. Unless the yeast has been generically modified to carry a certain trait down, which I know is not the case as they would be banned from the European market (where I reside), I don't think it's plausible to make such a claim.

There is obvious gain for them for making this claim but no real science to back it up.

FYI the yeast I was able to reuse was m20 Bavarian wheat and m41 Belgian ale. Both styles incidentally were yeast forward (hefeweizen and Belgian Golden Strong respectively).

 

[BrewnWKopperKat]

FYI the yeast I was able to reuse was m20 Bavarian wheat and m41 Belgian ale.

Thank you!

 

[BrewnWKopperKat]

Despite my anectodal claims which basically amount to nothing in the grand scheme of things. I just don't see the science here.

Some of the Homebrew Talk speculation around MJ strains is that 'they (or some of the strains)' may be a "blended" yeast product.

And part of the enjoyment of home brewing can be discovering that one can "break the rules" (actually guidance/recommendations) that yeast providers offer.

 

[Velnerj]

Some of the Homebrew Talk speculation around MJ strains is that 'they (or some of the strains)' may be a "blended" yeast product.

And part of the enjoyment of home brewing can be discovering that one can "break the rules" (actually guidance/recommendations) that yeast providers offer.

I see, so the idea is if there is a yeast blend then one (or more) strain(s) would shift into the background or foreground and make for a different flavor profile after a certain number of fermentations (generations).
I don't think you'd run into this problem after 1 iteration as per my experience. But certainly down the road if it is indeed a blend you could detect a drift. But perhaps for the better?

 

[Vale71]

They have a "contact us" page: Submit a request – Mangrove Jack's

Yeah, I'm sure I'll get a detailed explanation out of them and not just the marketing catchphrase you quoted before...

 

[BrewnWKopperKat]

I don't think you'd run into this problem after 1 iteration as per my experience. But certainly down the road if it is indeed a blend you could detect a drift. But perhaps for the better?

Perhaps for the better, and hopefully reproducible. Some of the dry yeast brands that talk about re-pitching do suggest an upper limit to the times one can reuse the yeast. IIRC, brewers over in the AHA forums talked about being able to reuse the yeast beyond those suggested upper limits.

There may be an interesting winter time activity in this: some yeast lab equipment, a bunch of different dry yeast strains, a big bag of DME, and a bunch of canning jars. And who knows, maybe a /r/homebrewing lurker reading this will post results over there next spring.

can I reuse dry yeast?

Lallemand has a PDF on Best Practices – Repitching using dry yeast on a "Downloads" page (Downloads – Lallemand Brewing).