Beers not fermenting down low enough

[zachattack698]

So I've done a bunch of all grain batches some ive done starters for and others I haven't but every time even if I use a starter it seems to stop fermenting around 1.025-1.020. I'm currently fermenting a dark saison looking for around 1.007 and it seems to be once again stuck at 1.020ish again. This is frustrrating an I can't seem to figure out why it keeps stopping any help or feedback would be awesome!

 

[wonderbread23]

Have you calibrated your thermometers? Perhaps you're mashing high. What is your grain bill? Are you using the Saison Dupont strain (Wyeast 3724)? That particular strain can take MONTHS to finish.

 

[duboman]

So I've done a bunch of all grain batches some ive done starters for and others I haven't but every time even if I use a starter it seems to stop fermenting around 1.025-1.020. I'm currently fermenting a dark saison looking for around 1.007 and it seems to be once again stuck at 1.020ish again. This is frustrrating an I can't seem to figure out why it keeps stopping any help or feedback would be awesome!

First off, what temp are you mashing at and are you sure your thermometer is properly calibrated? You could be mashing higher than you think.

Second, what yeast and temp profile are you using? You mention currently a Saison, they like it hot and sometimes can take forever to get to FG after a rapid start!

 

[zachattack698]

Using French saison yeast. Don't think I'm mashing to high as I have a few thermometers that I use to check temps to be safe. I even added yeast nutrients with 10 mins left in the boil. Also the basement I have it in is normally a solid 70 degrees at all times.

 

[duboman]

Just because you are using several thermometers does not mean they are accurate you also didn't provide a temperature

70 may not be high enough for the yeast either, the last Saison I did started at 80 and finished at 95, took 4 weeks to reach FG

Raise the temp and rouse the yeast and be patient

 

[zachattack698]

I mashed low on this beer 148 for 75 minutes I believe.

 

[Demus]

Are you by any chance measuring FG with a refractometer?

 

[zachattack698]

Are you by any chance measuring FG with a refractometer?

Yup I am I made sure to check and calibrate it this morning read a perfect 1.000 with water.

 

[aiptasia]

Mashing aside, your best options for improving your efficiency are:

1) A good crush on the grain. This is vitally important. My LHBS performs crushes for us at no charge but it's a very coarse crush. I always have them do a second crush on my grains. This has improved my efficiencies from 70% to about 80% just on the crush alone.

2) For anything over 1.050, use a healthy amount of: Yeast nutrient (DAP based), servomyces and one minute of pure oxygen. I like brewing a lot of high gravity beers and this seems to always get me over the 1.020 stuck fermentation hump. I have a steel diffuser and stem O2 kit from Northern Brewer and just buy the little pure oxygen tanks from the welding supply areas of Lowes and Home Depot. A good one minute blast just after pitching the yeast is perfect for oxygenating the wort.

3) Switch to a grain tea for your roasted and specialty grains. For any of your grains that don't require mashing (anything roasted, crystal malts, etc.), put them into a big sanitized grain bag and soak them in two quarts of distilled water per pound for 48 hours. Swish and dunk the bag a few times a day and keep a lid over the tea container, then just remove the grain bag and you have a very mellow grain tea left over. This extracts all of the roasted sugars without any of the tannin and astringency producing compounds. Add your tea to your boil at any temperature without worry about extracting anything astringent.

4) Always mash on the low side. I prefer around 150f for 75 mins. Never ever let the mash get over 160f or you'll halt the sugar conversion process and get a terrible extraction/efficiency. I never do step mashes as temperatures are too hard to dial in and hold on my setup. YMMV. Also, even if my thermometers are off calibration by +/- five degrees, it's no big deal at 150f.

5) Keep a few lbs. of extra light LME on hand if something goes completely wrong. If you're way off target on your OG, you can always return the wort to boil for a few minutes and add a cup or two of LME to the wort to bump up the OG.

 

[beaksnbeer]

What was your starting O.G.

 

[Moerdertaktiken]

Yup I am I made sure to check and calibrate it this morning read a perfect 1.000 with water.

Now i'm no refractometer expert, and i've yet to use one, but I was under the impression that they were only used pre-fermentation. I thought the alcohol throws off the reading making it inaccurate?

 

[zachattack698]

what was your starting o.g.

1.055

 

[bgs8884]

Now i'm no refractometer expert, and i've yet to use one, but I was under the impression that they were only used pre-fermentation. I thought the alcohol throws off the reading making it inaccurate?

I thought the same

 

[Nico93]

I know it's Italian but you can use Google translate
http://www.maxbeer.org/ita/uso_rifrattometro.htm
Here you can find the instructions to use a refractometer after the start of the fermentation
In the end of the page there is a excel page that may can help you

 

[zachattack698]

Now i'm no refractometer expert, and i've yet to use one, but I was under the impression that they were only used pre-fermentation. I thought the alcohol throws off the reading making it inaccurate?

Was not aware of this and I believe this was my error after using a calculator I've come to find out my beer is actually at 1.0065 which is perfect! Thanks for all your help everyone!

 

[govner1]

Using French saison yeast. Don't think I'm mashing to high as I have a few thermometers that I use to check temps to be safe. I even added yeast nutrients with 10 mins left in the boil. Also the basement I have it in is normally a solid 70 degrees at all times.

If you're doing a Saison w/ 3711 raise your temp closer to 80.

 

[Demus]

Yup I am I made sure to check and calibrate it this morning read a perfect 1.000 with water.

This is the problem. Read up on refractometers and you'll see they measure no gravity but, refraction. They are calibrated for a sugar solution so they are great for wort but one fermentation occurs the alcohol throws off the way light is refracted making the number invalid. You can still use it if you use one of the spread sheets on line, but I found it to be a pain. I think you find it under Sean Terrill. The good news is, I bet your beers have been fermenting down to much lower FGs than you think. Do they taste good? If they've tasted good than I can say with confidence it's ur refractometer to blame...

 

[davemattb]

So you are using a refractometer for FG right? Are you calculating the conversion when doing so? You cannot check final gravity with a refractometer without doing the calculation. The fermented beer refracts light different than unfermented wort. If im not mistaken, the Gravity is lower than the refractometer shows. I usually just check with a hydrometer now. That way I have a sample to taste...