Yeast question

[distantdrumming]

I'm only on my second batch, but each time there's been no fermentation activity for about 3-4 days. To the point where I start to get concerned. I've used rehydrated dry ale yeast both times at a well controlled temperature in the 62-64 degree range. First time I have to admit my aeration wasn't optimal, but this second batch was aerated well and took even longer to begin fermentation. I really don't want to get complex with stir plates (or whatever) I just want a healthy yeast with good fermentation. Any suggestions?

 

[jekeane]

I didn't notice a big change in my lag times until I started using an O2 wand with a disposable tank. When I went from shaking to pure 02 I went from 2-3 days lag to 4-8 hours.

62°-64° is also a little cold for many yeasts to get started in. I generally pitch at 66° and leave it there or let it rise to 67°-68° the only time I pitch below ales 64° is with a pretty big starter and its generally only kolsch or Alt yeast strains.

 

[IslandLizard]

You don't need a stir plate and starters when using dry yeast. Rehydration is good, more live cells available!

As @jekeane said, 62-64F is a bit low. I ferment most ales at a minimum of 65F, then raise to low 70s when it's almost done to keep the yeast going.

+1 to the oxygenation, more so with higher gravity beers.

If you get one of those O2 bottles, after applying oxygenation, remove the "regulator" from the bottle. That way, you can get 20+ batches out of 1 bottle. All those regulators leak a small (unmeasurable) bit, and over time your bottle drains empty.

 

[jrodmfish]

How do you know fermentation isn't happening?

 

[Kent88]

Pure oxygen is, IMHO, overkill unless you're brewing a really strong, high gravity beer. Your temps are probably a bit low. How much and what kind of beers are you making?

Feel free to shake the fermenter (as much as is possible without breaking something or making a mess) every few hours as long as krausen hasn't started. Be careful because this also de-gasses the wort which could make everything foam over. Also, keep your ales at right around the 65F range unless you start using liquid yeasts like those intended for kolsch.

 

[distantdrumming]

So it seems the consensus is my fermentation temp is too low. I've been doing 5 gallon batches. First was an IPA, this second is a SMASH that I made up. Can a temperature difference of just 2 degrees make that much of a difference in fermentation?

 

[jrodmfish]

I don't think temperature is necessarily the culprit. I don't know what yeast strain you're using but a quick look at a US-05 data sheet it says

fermentation temperature: 12-25°C (53.6-77°F) ideally 15-22°C (59-71.6°F)

Are you measuring the gravity to determine that fermentation isn't happening until 3-4 days?

 

[distantdrumming]

No, I'm not measuring the gravity. Just waiting for activity. I start measuring gravity after a couple weeks to see if it's done. I thought fermentation is pretty obvious. And I'm not sure if it's temperature either, but it's one variable I can manipulate and see. I kinda of think I'm not doing something to make it optimal for the yeast. Or maybe rehydrating it wrong, I don't know. I was actually really pleased with my aeration this last time and expected to see activity within a day or so.

 

[Sigvaldi]

What was your OG? Sometimes with higher gravities it can take longer to start, or the yeast can be stunted if there's not enough.

 

[stella_tigre]

Fermentation vessel - bucket vs carboy - can make a difference vis a vis apparent activity because of headspace and quality of seal of the vessel. Agree that temp and OG make a difference, in 1.055ish OG and happily rehydrated yeast, just aerating using air bubble or vigorous stirring, I normally see activity in 12-24 hours. Make sure your yeast is tempered after rehydrating so that pitch temp is no more than 10 deg less than the yeast temp. (Yeast solution at 70, wort is no less than 60, for instance.)

Edit, rereading original post, are you rehydrating the yeast at 62-64 degrees? Yeast rehydration usually needs to be in the 80+ degree range to wake it up happily. Depends on the yeast, manufacturer's recommendations are best followed for good results.

 

[distantdrumming]

OG was 1.057 with my first batch and 1.061 with this current one.i just used one package of of dry yeast each time US-05 and American West Coast

 

[distantdrumming]

I don't check the temp of the yeast when rehydrating cause I don't want to mess with it much, feel th outside of the container it's in. When it feels close to room temp I put yeast in to rehydrated. Wort is usually at around 70 when I pitch

 

[Sigvaldi]

That level of gravity doesnt seem like it would affect it much. Some fermentations can take longer. Like stella said, headspace can make a big difference too.

My current brew took 2 days for real noticeable airlocm activity to begin. Sometimes it just takes longer.

Knowing what yeast you used helps too. The instructions for safale us-05 are:

Sprinkle the yeast in minimum 10 times its weight of sterile water or wort at 27°c ± 3°C (80°F ± 6°F). Leave to rest 15 to 30 minutes. Gently stir for 30 minutes, and pitch the resultant cream into the fermentation vessel.

So it looks like temp may have been an issue and the yeast may not have really gotten a good start. This may be delaying them. I believe they will ptobably still start up, just take a little longer. Someone with a different experience?

 

[distantdrumming]

Yeah, I do have a decent head space. 6.5 gallon carboy with 5 gallons of wort. Should I be stirring the yeast when rehydrating? I've been afraid to touch it...I stir it up really good with a sanitized spoon then leave it alone for a good 15-30 minutes before pitching. I'll try a little higher temp next time, maybe 66, and see what that does.

 

[stella_tigre]

Yeah, I do have a decent head space. 6.5 gallon carboy with 5 gallons of wort. Should I be stirring the yeast when rehydrating? I've been afraid to touch it...I stir it up really good with a sanitized spoon then leave it alone for a good 15-30 minutes before pitching. I'll try a little higher temp next time, maybe 66, and see what that does.

From the Safale US-05 data sheet:

"Rehydration instructions
Sprinkle the yeast in minimum 10 times its weight of sterile water or wort at 27°C ± 3°C (80°F ± 6°F). Leave to rest 15 to 30 minutes.
Gently stir for 30 minutes, and pitch the resultant cream into the fermentation vessel.
Alternatively, pitch the yeast directly in the fermentation vessel providing the temperature of the wort is above 20°C (68°F). Progressively sprinkle
the dry yeast into the wort ensuring the yeast covers all the surface of wort available in order to avoid clumps. Leave for 30 minutes, then mix the
wort using aeration or by wort addition."

While they allow for sprinkling directly on the wort, I personally have much quicker results rehydrating and so always go that route.

Danstar recommends 30-35*C for AWC, so it won't like the cooler temps at rehydrating time. It's also known to be a bit of a slow starter. http://www.danstaryeast.com/company/products/bry-97-american-west-coast-beer-yeast

 

[distantdrumming]

I think I might just be impatient. Both my batches so far have fermented well from what I can tell. Just took a little longer than I expected from my readings elsewhere. What's that expression of Papazian? Something like chill out and drink a home brew Y'all have an acronym for it...I'll try my best not to freak when I check on the batch I brewed today in the morning and it's not fermenting yet Cheers, and thanks everyone