When is FG too low and should I bottle?

[Twopan]

I have a Bière de Garde in the FV. Extract brew ingredients from Brew UK including Wyeast Saison liquid yeast. 13.5 litres actual volume, OG was 1.056 and stated target FG should be 1.011. Now on day 13 and gravity still dropping albeit more slowly, currently 1.009 at 19°. ABV 6.1%. Interestingly the OG was not high enough to achieve the claimed ABV of 6.9% if it had stopped at 1.011. However, 6.1% is fine by me. Question as ever is, is it safe to bottle? If it drops even further am I risking off flavours? Thanks

 

[Twopan]

I have a Bière de Garde in the FV. Extract brew ingredients from Brew UK including Wyeast Saison liquid yeast. 13.5 litres actual volume, OG was 1.056 and stated target FG should be 1.011. Now on day 13 and gravity still dropping albeit more slowly, currently 1.009 at 19°. ABV 6.1%. Interestingly the OG was not high enough to achieve the claimed ABV of 6.9% if it had stopped at 1.011. However, 6.1% is fine by me. Question as ever is, is it safe to bottle? If it drops even further am I risking off flavours? Thanks

I should have added that airlock activity stopped after day 8

 

[An Ankoù]

You might not be risking off flavours, but you're risking burst bottles. Many saison yeasts have very high attenuation with some having the diastaticus variant. Wait until the fermentation is finished and the SG stable before bottling.
I'm not a saison expert by any means, but your FG still seems a bit high and some saison yeasts are notorious for stalling before picking up again-or so I've read.

 

[Twopan]

@An Ankoù many thanks. It has declined absolutely steadily so unlike others (non-Saison yeast) I have done where I get rapid gravity decline over 4 days and then practically nothing for another 10 days, creeping down agonisingly slowly. This one is a perfect curve and now 84% attenuated. I shall leave another 24 hours and check progress again.

 

[dmtaylor]

Best advice is to wait until you are certain it's finished (no more curvature!), then wait ANOTHER 3 or 4 days, just to be on the safe side. This is the way to avoid overcarbonation and gushers, unless you enjoy that sort of thing.

 

[Sadfield]

As above. It looks like the predicted FG of 1.011 is a misprint. 6.9% from 1.056 would be a FG of 1.003-4, which is in line with what I'd expect from Wyeast French Saison.

 

[Jim Brewster]

A Saison yeast should get quite low. Bear in mind that if your OG was lower than predicted then the FG will also be slightly lower.

6.1% Saison sounds great to me, I wish I had some in supply.

 

[dmtaylor]

Jeez, I didn't even look at which yeast you used. If it's 3711, you'll end up with 1.002 regardless of anything else you do to the recipe. And it will take about 3.5 weeks to get there. It keeps going and going, slowly, in my experience. Patience is necessary with this yeast strain in particular.

 

[DavidDetroit]

The makers should put a big warning label on the diasticus strains. I suppose they're great if you already know what you're doing. For a new brewer, there are already enough moving parts to deal with.
I know that if I had stumbled across a recipe that required that strain when I first started, I would have blown up 35 flip-tops as I would have been doing the mechanical "one week in primary, one week in secondary" kind of thing without understanding the yeast's properties.

 

[Sadfield]

The makers should put a big warning label on the diasticus strains. I suppose they're great if you already know what you're doing. For a new brewer, there are already enough moving parts to deal with.
I know that if I had stumbled across a recipe that required that strain when I first started, I would have blown up 35 flip-tops as I would have been doing the mechanical "one week in primary, one week in secondary" kind of thing without understanding the yeast's properties.

Totally. They go to some lengths with commercial breweries with regards to literature and seminars on dealing with diastaticus, and best CIP and testing practice to avoid contamination. With homebrewers, nothing. I do wonder when you see post about gushers or over carbonation, if saison strains have been used previously. I did question a Lallemand rep about sanitation, when homebrewers aren't using hot caustic, which he acknowledged was something he needed to look into, but never got back.

 

[DavidDetroit]

With homebrewers, nothing.

That's what I experienced. I didn't even know what "diastaticus" was until about three years ago. Lucky me for coming here to learn about it. I used it once by accident, mentioned it in a post while talking about something entirely unrelated and got a "did you know..." fortunately.
I wouldn't be surprised about the gushers.

 

[JonathanMSE]

Totally. They go to some lengths with commercial breweries with regards to literature and seminars on dealing with diastaticus, and best CIP and testing practice to avoid contamination. With homebrewers, nothing. I do wonder when you see post about gushers or over carbonation, if saison strains have been used previously. I did question a Lallemand rep about sanitation, when homebrewers aren't using hot caustic, which he acknowledged was something he needed to look into, but never got back.

Yup. I've certainly had a few gushers after reusing bottles that had previously contained a beer with belle saison in it.

(And the ones that gushed tasted very dry compared to the ones that didn't)

If I've used a diastaticus strain I'll soak bottles with a really strong batch of VWP for 24 hours, then go through rinsing and sanitation as usual, but I'll leave a longer contact time with the sanitiser, 20 mins or so.

It seems to work for me and no more gushers as a result.

 

[Sadfield]

Luckily it was Saison that got me into brewing, my first brew using Belle Saison, so I knew that they were super attenuating yeasts and what to expect to some degree, although not the finer details of var. diastaticus.