Constant Fermentation Issues

[Iamslow]

Gents, I really am slow and can't seem to tackle this fermentation hurdle I keep running into. I have brewed both Extract and All Grain brews and cannot get my beer to ferment down to the correct final gravity. https://cdn.homebrewtalk.com/images/smilies/mad.gif

All brew sizes are 5 to 5.5 gallons

They all stall out around 1.02 or 1.018 and my latest is stuck around 1.024.

I've learned something on each beer, but I'm tired of learning and want to skip to getting it right so I need some advice from the pros.

1st beer (APA) (partial mash) that stalled I learned I didn't pitch enough yeast. (OG 1.065 FG 1.020)

All beers since I've used a stir plate and use mrmalty and beersmith to get correct starter sizes (I even up that a bit to make sure I have enough yeast)

2nd beer (IPA) (All Grain) brewed and again ended at 1.020. Realized, pouring wort through strainer and shaking the crap out of it to aerate wasn't going to do the trick. (OG 1.068 FG 1.020)

3rd beer (Heff - EdWort's Bavarian) (All Grain) This time I used pure O2 with stainless steel diffusor for two min to add air. Two minutes at just enough to see bubbles at the top. That had to be way too little time because my freaking heff didn't even ferment out. (SG 1.045 FG 1.020)

4th beer (Imperial Stout - BigBen's IrishDeath Clone) (All Grain) This time I aerated by running beer through strainer then shaking the crap out of it for 3 min. Then I aerated with pure O2 for 4 minutes. Thinking I'm good right? Used WLP 004 with 2L starter. (SG 1.075)

This is where it gets interesting. Was cleaning up and instead of hooking up the blow off tube right away I just put the airlock on and started clean up (it was a 6.5 gal carboy). After cleanup I sat on the couch then went to bed forgetting about the beer. Oops. Wife complained all night of hissing noise, but I couldn't hear and didn't think anything of it. About mid day the next day the airlock blew off, which of course hit the ceiling, walls, and white carpet with black beer and pissed off SWMBO. There was a lot of scrubbing to clean that one up.

Anyway, I thought for sure this one would hit its mark, but I measured the gravity (hydrometer) and this one is only at a 1.024, supposed to be 1.018. WTF!?@?!?!?

All beer was fermented in a room where the ambient temperature ranged from 64-70. Is there something obvious I am doing wrong? Should I be fermenting the beer in the first few days at a lower temp to account for the yeast heating the beer up?

My next things to try:
1. Even though I believe I am hitting my correct water ph and characteristics I was thinking of starting my next with RO water and build to guarantee I am perfect.
2. use dry yeast since I've only ever used liquid WLP.

I need some help, I love this hobby and don't want to give up, but I'm getting a bit discouraged. I appreciate all the advice and sorry for the long post.

 

[TNTgill]

What were your mash temps for these brews and are you sure your thermometers are calibrated? High mash temps will create a less fermentable wort and not reach the FG you are looking for. I'm far from a pro but that would be the first info I would want when trying to troubleshoot this issue.

 

[ICWiener]

Sounds like you're doing a lot of work that should be netting positive results. Chances are, your water's fine. I wouldn't mess with that. The only things I would say are:

A) Watch your fermentation temps, make sure you're staying in the correct range for the yeast you're using.

B) Mash your next beer at 146-147F, go light on the specialty grains, and add 5-10% dextrose or table sugar to the boil (that's how I make my saisons, which finish out below 1.010). That should help maximize your fermentability. If you can't get a beer like that to finish low, then either there's something wrong with your process or.....

C) You need to buy a new hydrometer. And make sure you're checking your gravity at a good temp. Close to 60F. This is where I would look first if I were you.

 

[Iamslow]

Mash temps for my last brew were spot on. I have missed by two degrees in the past, but only on the low side. You did get me thinking, how do you know if your thermometer is accurate. Mine hits 213 with boiling water, but that's about the only way I could think of testing it.

I wish my hydrometer was the issue, but I was given another from a friend to try out and it reads the same.

I've never done the table sugar addition. I may have to read up on that to see if that works.

Thanks for the input

 

[ICWiener]

You did get me thinking, how do you know if your thermometer is accurate. Mine hits 213 with boiling water, but that's about the only way I could think of testing it.

Put the thermometer in a jar full of ice, topped up with water. It should read 32F.

 

[tre9er]

How much specialty grains are in these brews? Mash temps, again, are the other factor. The yeast, even with crappy O2 and underpitching, should still eat most of the sugar in there, provided it's fermentable sugar. I, like most, have run the gamut on stupid rookie mistakes, but I've never had a beer stall or fail to get at least close to FG. Mash temps are one thing that I haven't overshot by much, but I've underoxygenated, underpitched, fermented high, etc.

Lastly, there's a remote possibility that if you ambient temperatures fluctuate, once the yeast is starting to die down a bit if it experiences a cooler temp than previous, it can tend to flocc out prematurely. Try putting fermenters in a swamp cooler to buffer ambient temp changes, or controlling ferm temps more precisely with a ferm chamber.

 

[Iamslow]

tre9er - do you think a bathtub full of water sitting around 68 would hold the internal temp of the fermenting beer down as the yeast are doing their thing creating the heat or is that heat natural? Wife is going to love taking up the bathtub, but I need my beer and she does love to drink it.

Yes, there were specialty grains in each, but no more than the recipe and others seem to hit their FG just fine.

 

[tre9er]

Yes, the bathtub or a rubbermaid container would help buffer ambient temp changes. When the krausen starts to fall I'd let the beer free-rise to a slightly warmer temp, as the chance for off flavors is almost nil by then. What you don't want is a temperature decrease as the yeast starts to flocc, or it could fall too quickly.

Still, lower mash temps, reducing unfermentables like some specialty grains, lactose, etc, oxygenation, healthy yeast cell counts, and controlled fermentation temps (avoiding swings) should almost always ferment to "full" attenuation.

 

[ICWiener]

Oh, and make sure your vials aren't old as hell. If you're unknowingly buying expired yeast, that can't be helping.

 

[adamdillabo]

I have this problem too. My solution: I stopped taking gravity readings.

 

[kblankenship11]

This definitely sounds like a puzzler. But looking at your OG and FG readings from your first two beers, they do not sound too bad to me. The first 2-4 beers that I did without getting my oxygenation/pitching rates where they needed to be, were at least 4-5 points higher than the expected FG from the recipe. Nothing earth-shattering there.

The third beer you did definitely finished high. It was oxygenated; but what was your pitching rate, mash temps and ferment temps? Need a bit more data there.

The fourth beer is a beast at an OG of 1.074. You say it's currently at 1.024, but how long has it been fermenting? If you're a week in the yeast probably aren't done. But still, this doesn't sound too horrible to me. The last huge beer I made which was a Doppelbock had an OG of 1.083 and finished at 1.022 (the recipe said it would finish at 1.023), so I don't think your numbers are horrible.

I think you need to go back to basics and make a simple APA taking very good notes of your process from start to finish. Find a recipe that's mainly 2-row with a bit of crystal and mash at the high 140's. I would use a packet US-05 yeast, which is always fail-safe. Oxygenate as you normally would and ferment in the upper 68-70 range. Keep a good eye on your fermenters temperature and watch for fluctuations. If you can, try to bring the temp up during the end of fermentation to make the yeast a little happier. I would find you hard-pressed not to have a beer like that ferment out as expected.

 

[Iamslow]

Yeast has been really fresh, typically a week or two old, but I've always wanted to give teh US-05 a try since I never heard anyone have issues with that type.

I will brew something simple this weekend and post an update of how it goes. If all else fails, I may become a follower of adamdillabo.

Thanks again for insight.

 

[Iamslow]

Sorry it has taken me so long to post the result. I just had a baby girl and I fogot how much time the little ones take up. Eventually I did make it to the garage and brewed up a batch of Ed Wort's Haus with Citra instead of Cascade.

Taking the advice from this forum I fermented in the bath tub at a temp of 65-69 (Nottingham - accidently pitched Notti instead of US-05) for 10 days. It started out a lot slower than my other batches, but hooray this one actually made it below the 1.020 barrier. Started at 1.058 and fermented down to 1.010. Thanks again for all the input on this one. I might have to change my name to NotAsSlow if the next one turns out just as good.

Thank you

 

[Omahawk]

Started at 1.058 and fermented down to 1.010.

Holy cow. You went from one attenuation extreme to the other.

Congrats on the addition to your family.