S-04 stalling?

[00Seven]

S-04 in my last 2 beers has been stalling on me right around 1.015. First one had 70% attenuation after 2 1/2 weeks fermentation, second one stalled at the same gravity but with only 64% attenuation and 2 1/2 weeks fermentation. I was always careful to pitch below 80 degrees and rehydrated my yeast and made sure it was active before pitching. Kept fermentation around 66-68 for 3 days then finished out at 72. Any ideas

 

[IslandLizard]

After gone through a similar agony as you, I've concluded it had to do with either lack of sufficient oxygenation and/or a temperature drop during fermentation. S-04 seems to really dislike a temp drop toward the end. I was unable to resurrect it. The 1.090-some Old Ale got stuck at 1.031 for 2 weeks, whatever I tried, it never resumed. That was with 2 rehydrated packs pitched in a 5 gallon batch, and pouring the wort back and forth between buckets a few times.

Or perhaps to do with "Petite Mutantes."

 

[imasickboy]

Also, check your thermometer calibration. I use S04 a lot, and it always get my expected attenuation. I'm perplexed as to why you didn't.

In addition, I do not re-hydrate before pitching.

 

[couchsending]

When using dry yeast there is no need to oxygenate the wort. I’ve never had issues with it stalling but I’ve only used it 8 or 9 times. I’ve even fermented it at 59 and it finished just as fast as always.

Not sure what’s happening.

Are you rehydrating in tap water or RO/distilled?

 

[kh54s10]

Depending on recipe, 1.015 might not be stalled at all. I don't have all my FG numbers but I don't think S-04 has ever taken any of my brews below 1.008. More likely between the 1.015 you are getting and 1.010. How do the beers taste?

 

[00Seven]

Depending on recipe, 1.015 might not be stalled at all. I don't have all my FG numbers but I don't think S-04 has ever taken any of my brews below 1.008. More likely between the 1.015 you are getting and 1.010. How do the beers taste?

Well perhaps you’re right. American wheat I brewed I was hoping for it to drop a little lower abv coming in at 3.62. Which isn’t terrible but was hoping for a touch better. My SG was even a tad higher than I expected so I was excited. The IPA is 4.9% again is fine as it is a session ipa but with both beers I was hoping closer to 1.009. Ipa tastes great so no issues there

I can assure you I didn’t have a temp drop at the end. I’m in south Texas and it’s supposed to be 102 degrees tomorrow. My AC is running for 16 hours a day and the inside of my house is 78. I’m keeping it cool with evaporation in a water bath but can only do so much right now

 

[PADave]

When using dry yeast there is no need to oxygenate the wort. I’ve never had issues with it stalling but I’ve only used it 8 or 9 times. I’ve even fermented it at 59 and it finished just as fast as always.

Not sure what’s happening.

Are you rehydrating in tap water or RO/distilled?

How do you figure this? What's special about dry yeast that they don't need oxygen? Sure you don't mean re-hydrate?

 

[couchsending]

Yup

Dry yeast is made with enough sterol reserves to replicate without the need for oxygen. Most dry yeast companies tell you not to oxygenate the first pitch of dry yeast but do so on subsequent generations.

Any time you can avoid adding O2 to your wort I would recommend it. One of the few benefits of dry yeast.

 

[imasickboy]

Yup

Dry yeast is made with enough sterol reserves to replicate without the need for oxygen. Most dry yeast companies tell you not to oxygenate the first pitch of dry yeast but do so on subsequent generations.

Would you be so kind as to provide a source for this tidbit, please?

 

[couchsending]

Would you be so kind as to provide a source for this tidbit, please?

Google it

It’s all over everywhere. Thought it was common knowledge. Probrewer is a great resource, I generally start there.

 

[couchsending]

https://fermentis.com/tips-n-tricks/questions-and-answers/

 

[imasickboy]

https://fermentis.com/tips-n-tricks/questions-and-answers/

Thank you.

 

[beermanpete]

It seems that Fermentis provides contrary information about aeration. In the tips-n-tricks page referenced by @couchsending they advises not to aerate but in their S-04 product description sheet they suggest to aerate as a method of mixing in the yeast. I guess we each have to decide which to follow.

REHYDRATION INSTRUCTIONS:
Sprinkle the yeast in minimum 10 times its weight of sterile water or wort at 25 to 29°C (77°F to 84°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.

https://fermentis.com/wp-content/uploads/2017/10/SafAle-S-04.pdf