Sefale US05 caused FG 1.006 (1.5p)! What is the reason?

[Miles_1111]

My last batch was an IPA using US05 yeast. Its OG was 1.064 (15.6p), while after 3 weeks in the fermentor ( 20°C/68°F, including dry hopping 1 week) the actual FG was 1.006 (1.5p)! which is supposed to be around 3p (1.012)..

They say it is because my last batch was a Saison, the Saison yeast somehow came into this batch. Does it make sense? I thought it was because my mashing temperator was low 65°C/149°F.

Any comments? Thank.

 

[thehaze]

I'd be suspicious of US-05 getting 90% attenuation.

If you brewed a Saison before, that might explain it. Saison yeast are Diastaticus and will only stop fermenting when no sugars are left in the beer. That can take time, but it will get there. Most time, phenols are developed in a Diastaticus contamined beer. I've used Saison yeasts, but never had issues. Cleaning, desinfection and sanitation must be in order, to avoid problems.

But have you tasted the beer? What kind of aroma and taste do you get from it?

 

[Iseneye]

65 degrees mash probably isn't going that low with 05. Is your reading reliable?

 

[thehaze]

I never had US-05 go under 1.007 and this was a beer I mashed looong, looow and added sugar. So I don't think your mash schedule did that.

But have a taste and tell us what you can pick up.

 

[dmtaylor]

Why are you measuring in Plato? Homebrewers generally don't do this. How are you taking measurements? Hydrometer, or refractometer? Are you using conversion software to go between SG and Plato? How are you doing this?

 

[friarsmith]

Perhaps the thermometer measuring mash temp is off and your mash was lower than 149. Have you checked it against another?

 

[Miles_1111]

I'd be suspicious of US-05 getting 90% attenuation.

If you brewed a Saison before, that might explain it. Saison yeast are Diastaticus and will only stop fermenting when no sugars are left in the beer. That can take time, but it will get there. Most time, phenols are developed in a Diastaticus contamined beer. I've used Saison yeasts, but never had issues. Cleaning, desinfection and sanitation must be in order, to avoid problems.

But have you tasted the beer? What kind of aroma and taste do you get from it?

I tasted a bit before bottling and it feels extremely dry but not much Saison flavour.. I will pay attention to it when it is ready to drink which will be in 8 more days.

I did the cleaning with PBW and sanitation with Starsan, so I thought the equipment has been taken care of properly. However, I did not use small brush to clean the inside of the tubes. Maybe the Saison yeast stick into the inside of it? Is there any chance the Saison yeast stayed in my brewing room, for example in the air?

 

[Miles_1111]

65 degrees mash probably isn't going that low with 05. Is your reading reliable?

I think so, but next time I will use another Hydrometer to double check. I tasted it a bit before bottling and it felt much dryer than another batches.

 

[SEndorf]

The Saison yeast contamination would need to be more significant than this.
I suspect a measurement error .

 

[Miles_1111]

Why are you measuring in Plato? Homebrewers generally don't do this. How are you taking measurements? Hydrometer, or refractometer? Are you using conversion software to go between SG and Plato? How are you doing this?

The Hydrometer I normally used is reading in Plato, but I have another one in 1.000.. and next time I will use both of them to double check. Yes, I did the conversion by an online software which I believe is reliable.

 

[AZCoolerBrewer]

I have segregated blow off tubes and transfer tubing, because the blow off tubes sit around with blow off in them they get all yellow and are hard to clean without a brush and even then I still wouldn’t use them to transfer. My racking tubing is cleaned immediately after racking and then sanitized. They look very clean, not discolored after they dry hanging up. I have also never used a Saison yeast, so I don’t know if my sanitation game is strong enough to keep stuff from contaminating my beer.

 

[FatDragon]

I've definitely had US-05 drop this low. Was I getting a Diastaticus infection from previously using Belle Saison in the same fermenter? Maybe, but other yeasts haven't gone that low in the same fermenter, so I doubt it.

I also use Plato, by the way. Here in China most hydrometers don't have SG markings, so I have used Plato ever since my first imported hydro broke. It's about a dollar for a Plato hydrometer and maybe seven or eight times that for an imported SG hydrometer. Not really worth it. I can always calculate the SG from Plato if I ever need to.

 

[Dland]

I've had 05 work down to 1.006, and it was good beer, if on the dry/crisp side, this is usually result of lower mash temps and fully fermentable grain bill.

 

[Miles_1111]

I've definitely had US-05 drop this low. Was I getting a Diastaticus infection from previously using Belle Saison in the same fermenter? Maybe, but other yeasts haven't gone that low in the same fermenter, so I doubt it.

I also use Plato, by the way. Here in China most hydrometers don't have SG markings, so I have used Plato ever since my first imported hydro broke. It's about a dollar for a Plato hydrometer and maybe seven or eight times that for an imported SG hydrometer. Not really worth it. I can always calculate the SG from Plato if I ever need to.

Wow, did not expect meeting someone in China here. I am in China too, but Beijing. Acutally I have another hydrometer which can be read in Plato and SG at the same time. I bought it on Taobao at Manpin store( 慢品) and I just checked they still have it in store.

 

[dmtaylor]

It's likely contaminated by diastaticus. It happens, even to big breweries.

 

[hottpeper13]

A yeast cross contamination in the fermenter likely won't be realized until the beer is in the final package. That is where the macros are having issues(can and bottle explosions). You said loooong and loooow, I do overnite mashes sometimes(~6hrs) and I'll get 85% ADF with just about any well attenuating yeast.

 

[FatDragon]

Wow, did not expect meeting someone in China here. I am in China too, but Beijing. Acutally I have another hydrometer which can be read in Plato and SG at the same time. I bought it on Taobao at Manpin store( 慢品) and I just checked they still have it in store.

Nice. I might pick one up from them on a future order. They've always been my first stop for most brewing stuff, and my current hydrometer came from them, albeit bought a few years ago.

I assume you're using their repackaged US-05? That's my primary source of US-05 too. I wonder if there's any chance that it picks up some impurities in their repackaging process that would explain the low FG, since I often get OGs in that range myself.

 

[Dland]

I get my 05 in normal Fermentis packets. I sometimes re pitch if timing is spot on, working hard in the other fermentor, otherwise not, and never more than a few cycles.

Looked back though my brew log, usually have been getting 1.008-10, but was down to 1.006/007 a few times.

I'll be first to admit my cheap hydrometers could be off a point or two, but my brew notes indicate those beers were on the dry side, and they were ones when I was messing with 140F mash ins and simple grain bills.

 

[Miles_1111]

It's likely contaminated by diastaticus. It happens, even to big breweries.

If it is contaminated by diastaticus,
1. is it from the Saison yeast?
2. is it contaminated by air borne or only throught equipments?
3. how can it be proved? By tasting it? What flavour should I expect then?

Thank you.

 

[Miles_1111]

Nice. I might pick one up from them on a future order. They've always been my first stop for most brewing stuff, and my current hydrometer came from them, albeit bought a few years ago.

I assume you're using their repackaged US-05? That's my primary source of US-05 too. I wonder if there's any chance that it picks up some impurities in their repackaging process that would explain the low FG, since I often get OGs in that range myself.

Actually I was using repackaged yeast before, but since I had some fermentation problems, I started using original package imported, like this batch.

Now I am buying stuff from 超级麦芽自酿啤酒（Super Malt Homebrewing Beer）in Taobao. They are really good and have more varity of malts, hops and yeasts. It is my first option when buying the ingredients.

 

[dmtaylor]

If it is contaminated by diastaticus,
1. is it from the Saison yeast?
2. is it contaminated by air borne or only throught equipments?
3. how can it be proved? By tasting it? What flavour should I expect then?

As covered previously, yes, saison yeasts are of the diastaticus type. I'd expect very low specific gravity, and pepper-like spiciness with possible other phenols and "Belgian" character.

 

[Tobor_8thMan]

FWIW, I used US-05 to ferment a peach hard cider when the Mangrove M02 didn't start up. Everyone who's drank the peach hard cider loves it and wants more!

 

[dreaded_rust]

I consistently get about 85-88% attenuation from US05 in my IPAs.
I mash about 150 and ussualy have about a pound of corn sugar in my recipes.

 

[Vader ipa]

I consistently get about 85-88% attenuation from US05 in my IPAs.
I mash about 150 and ussualy have about a pound of corn sugar in my recipes.

Couple questions.
1. Does adding the corn sugar add about 1% abv to the overall abv?
2. Does adding the corn sugar make your ipas drier?

 

[dreaded_rust]

1. Yeah, pretty close
2. Yes, a little bit

 

[SoCal-Doug]

We gotta stop the paranoia...

Having the STA1 gene in a yeast strain (diastaticus variant) does not mean it's going to sit around, survive a nuclear war, then come back to life and take over the world. It is still a yeast and lives, multiplies, and dies like any other yeast. It may be an ultra-high attenuator, and you need to be aware of that and plan for that, if you choose to use it. There is absolutely nothing to be afraid of when using yeasts with STA1. There is also no reason to not use them. If you are using 3711 or other STA1 yeasts, don't bottle it when it's at 1.012, it's most likely going to end below 1.005.

In a similar situation with oddly less paranoia, people that use brett, lacto, or pedio know that it is a slow bacteria and can take months to work. Just like an STA1 yeast, if you have an inadvertent or accidental infection with a souring bacteria, you might not find out for many weeks or months.

People probably get cross contamination all the time and never know it. Maybe a bit of lager yeast getting into an ale or vice versa. Maybe some Belgian funk shows up in a Kolsch or lager. Maybe they dont detect the esters, sulfurs, or phenols that really should not be in that particular brew.

High attenuation doesn't prove or diagnose a diastaticus infection. I've had 65% attenuators run to 80% and have had 75% attenuators die off at 60%. There are many other factors that can contribute to an unexpected FG.

Bottom line...

It doesn't matter what yeast or bacteria you use, you need to practice proper hygiene or it's going to eventually bite you in the a$$. One stray live cell of any yeast or bacteria getting into your wort, it's going to multiply and act on it if the proper conditions and food source exist. I like to tell new brewers to pretend everything that touches their wort is coated with a cold or flu virus and if they drink it, they will get the flu, so clean and sanitize accordingly

 

[JONNYROTTEN]

The beer I'm drink now went from 1.062 to 1.008 Lower than projected and the lowest I've ever gotten from 05 yeast. I thought it might be infected also but it not and is one fine beer. Nothing but 2 row and honey malt. Fermented a little high. Pitched at 74 and it took off by the next morning and was at 68. Finished in three days....I wont sweat 05 going that low again.

 

[brownni5]

I agree with So-Cal Doug. It's just yeast. Too much STA1 fear mongering.

 

[schematix]

I love using US-05 in my IPAs because it reliably gets so low. IMHO that's 1 of 3 secrets to making an epic IPA. My typical recipe is 97% 2-row, 3% crystal, OG of 15P and ends usually just under 2P (measured with reliable, precision instruments).

This is a very fermentable wort though. I use the same yeast in the yooper's oatmeal stout and it'll only eek out about 70% AA, but that beer is loaded with unfermentables, which is one reason it's so deliciously fattening.

I didn't see OP post a recipe... that might shed some more light on whether this is really a problem, or just a difference from what was desired.

 

[JONNYROTTEN]

I love using US-05 in my IPAs because it reliably gets so low. IMHO that's 1 of 3 secrets to making an epic IPA.

So whats the other 2 secrets? My IPAs are good but not epic...I want epic