Killervector

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Ok, here is the deal. I've been brewing for 17 years. I have always had attenuation problems.

I've used pure 02. I've used an aquarium pump. I've underpitched, I've overpitched. I'm always about 3-5 points short of where I want to be.

Not a huge deal in my most recent beer, but a problem nonetheless, since the problem is so consistent.

I made a dry stout. 10G batch. Used 2 smackpacks of Wyeast 1084 Irish Ale yeast. Oxygenated with pure O2 inline in my chill wizard. Pitched a little warmer than I would have liked, at about 78 because I couldn't get it to chill any further with the ground water at 78. I pitched right away, and put fermenters in my basement at 69. Fermented 17 days at 69. Went to secondary today, and am short on my FG. OG was 1.043-1.044. FG is 1.013-1.014 giving me a finished beer of 3.8% alcohol. Now, I was only shooting for 4.2%, but I still came up short. Not the end of the world, but annoying as hell! BTW, I mashed for an hour at 149 degrees.

Any tips? There has got to be SOMETHING I'm doing wrong here. I can't figure out what it is. It doesn't even seem to matter if I pitch on top of an old yeast cake immediately.

phatuna

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what yeast strain?

edit: sorry I see it now

jmo88

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Have you double checked your thermometer you use for mashing? It might be a good idea to invest in a good thermometer and calibrate it often.

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maida7

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You should make a starter. 2 pack is only half what would be required for that beer.

Check your thermometer. It could be off.

Mash thinner 1.5 quarts per lb

Mash longer 90 mins at 149F

check your mash pH

Yooper

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The first thing I'd do is double check the accuracy of the thermometer. If you mashed a beer, even a stout, at 149, it should be pretty fermentable wort.

The next thing I'd look at is the choice of yeast strains. Some yeast strains attenuate to 67%, some 80%. If you want greater attenuation, choosing a more attenuative strain will help.

By the way, a FG of 1.013 seems about right for a stout. I probably wouldn't want it any lower than that. If you want a higher ABV, the easiest fix would be to increase the fermentables next time- a higher OG will be an easy way to work around this issue.

As was mentioned, even with a low OG, two packages of yeast for a 10 gallon batch is underpitching. I'm not sure it's the issue, but it certainly didn't help.

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Killervector

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I hear ya guys. I use a Brewmagic system, so I'm pretty certain the thermometer is right. Also, this time I used Wyeast 1084, which means I should have gotten about 73%. IIRC. So, I think my attenuation this time was about 70%. It doesn't seem to matter what strain I use, and I've batch sparged with a cooler prior to the last 3 batches. No differnence.

Mash PH I assume is 5.2. Or, I use the 5.2 powder anyway. I don't have any ph testing equip.

portalgod

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From reading the first post, it sounds like you're considering the gravity when transferring from primary to secondary as your FG. I've noticed that while I drop the majority of gravity in the primary (after a few weeks), I still drop less than a handful of points while in the secondary. That is, gravity into primary could be 1.040, gravity after a week or two into secondary could be like 1.015, and gravity after another few weeks at bottling time could be like 1.011.

What's your gravity at bottling? Does it drop down into your desired FG range?

portalgod

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On second thought, I don't think I've ever dropped 4 points in secondary. Maybe just 1 or 2 or so.

Killervector

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Yeah, I've never dropped in secondary more than like 2 points. I don't bottle though, I keg. Also... I've almost ALWAYS use starters. This last time, i didn't because I was short on time, so I just bought another smack pack. I figured 2 smack packs in such a low gravity wort would be fine. I was only 1.043 or so to start.

samc

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You know the old saying about assuming things?


Best thing is to know what you've got, don't assume anything.