consistent final gravity issue

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heathcom

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I have done 3 or 4 all grain batches from stouts to ambers in the last month, I have been getting my target OG or atleast acceptable range from 1.050 and above depending on the style. Such as a belgian getting 1.070 and a brown at 1.050. I leave it alone in the fermenter for atleast 3 weeks at temps from 65 to 70. Last few readings didnt get over (or under?) 1.030. Still a decent beer but when I see other folks with 1.010 or better, I think maybe Im missing something.
Here is a slight breakdown of my process.
I use a victory grain mill at a gap the size of a credit card (.032 I think).
Mash at 154, give or take a degree, for 60 mins.
Batch sparge usually 3 runnings to get my target wort volume.
Boil 60 plus mins than cool to 75ish with a wort chiller.
Sprinkle dry yeast into wort and wait. Usually 30 mins to see activity.
Usually 2 weeks and the airlock has almost no bubbles.

Maybe iffy hydrometer or thermometer is off? I also use a whole packet for one gallon batches, maybe over-kill?
 
Forgot to mention, I pitched another slight sprinkle into one batch that is stuck at 1.032 24 hours ago and zero changes. No airlock bubbles or noticable clumps of anything.
 
are you aerating the wort? thats the only thing I could think of to keep your fg that high. I'd also double check your hydrometer with distilled water. it should read 1.0000 at 60 F. then check your thermometer in boiling water, it should read 212. in a glass of ice water it should say 32.
 
Thanks, I'll check the hydro. I use the thermo for boiling water and is over 200 so I think thats ok. I shake the fermenter vigorously for about a minute until its good and frothy. Maybe I need to either use a aquarium bubbler or shake the crap out of it longer.
 
I would hydrate your dry yeast. Pitcing on top of the wort kills lots of the yeast, could be your issue with higher OG worts.

I would also invest in an O2 stone, makes for much healthier fermentations.
 
I had an aquarium stone and pump from an old fish tank, stone is new and well sanitized. Tried about 10 mins and let some of the froth come over the top. I did rehydrate before pitching as well. Used a whole packet for 2 gallons. Shook the crap out of it too. We'll see how things comes out in a few weeks. OG was 1.070 :)
 
Based on personal experience and what I have heard from the yeast companies do not think rehydrating the yeast makes a difference, and even if it does, that alone would not have your 1.050 beers finishing at 1.030.

Your post seams to imply that this attenuation issue cropped up at the same time that you switched to all grain. Which to me implies not a yeast issue, but a wort fermentability issue (although it is quite possible that it is a combination of the two). Do you have any idea what your water is like? because that sounds like something you would get from a high mash pH, or a combination of high pH and less O2 than ideal for the yeast.

thats my two cents, look at the mash pH if you can.
 
I always have been all grain, I am new to brewing, started in january. I have just started taking more accurate readings now that Im more familiar with the process.
Other than not enough sugars and not enough oxygen to hit better FG, is that the jist of it?
The water I use comes from a well. It tastes like spring water but will give me something to check. Thanks for the input.
 
Thanks, I'll check the hydro. I use the thermo for boiling water and is over 200 so I think thats ok. I shake the fermenter vigorously for about a minute until its good and frothy. Maybe I need to either use a aquarium bubbler or shake the crap out of it longer.

over 200?

that could be your issue, if it's reading closer to 200 than 212 your mash temp could be reading 154 when its more like 166ish
 
Forgot to mention, I pitched another slight sprinkle into one batch that is stuck at 1.032 24 hours ago and zero changes. No airlock bubbles or noticable clumps of anything.

Not that it's specifically related to your issue, but you won't get a stuck fermentation to restart by just adding yeast. You need to make some sort of starter first.
 
over 200?

that could be your issue, if it's reading closer to 200 than 212 your mash temp could be reading 154 when its more like 166ish

That's what I was thinking. What kind of thermometer are you using? You really need it to be precise to within a degree or two at most.
 
It's the thermo. I had the same issues for a while but only in the other direction. Beer finishing at 1.003 is pretty thin!
 
Ph is 7.6 ish give or take a tenth, I think thats in the normal range. I use the thermo that came with a turkey fryer, also used a candy thermo that i had and compared the two, seem pretty equal. I will invest in a good food grade digital thermo next batch.
Wouldnt a higher mash temp end with a higher abv though?
 
Ph is 7.6 ish give or take a tenth, I think thats in the normal range. I use the thermo that came with a turkey fryer, also used a candy thermo that i had and compared the two, seem pretty equal. I will invest in a good food grade digital thermo next batch.
Wouldnt a higher mash temp end with a higher abv though?

Nope... Higher mash temp=less fermentables. FWIW, my turkey fryer thermo is 15 degrees off!
 
I bought a digital thermo and will compare that to the one Ive been using later tonight. I have been looking at the batch i just finished on sunday, had much activity for a full day and is now settling down. The batches from a week ago seem lifeless... Do darker beers tend to not ferment as well?
 
Beer color has nothing to do with the strength or length of fermentation. After a week most normal gravity ales are done with primary fermentation so there shouldn't be much activity that you can see.

Also, for your newest beer. 24 hours of vigorous fermentation can make anything else look slow and is perfectly normal.

Your OG, yeast pitching rates and fermentation temps will determine most of that activity.
 
I use a dry packet for small batches. Packets are good for 5 gallons so I know I have plenty to start. Maybe over pitching but I rehydrate for the ones that say to rehydrate and pitch on the wort when it says to pitch on the wort.
Assumptions at this point are mash temp too high or not aerating enough.
 
dry yeast doesn't require aeration so I doubt that's your issue

the other possibility although unlikely would be the composition of your grist - if you are using way too many specialty malts you can end up with a high FG as well but since it's happening consistently I assume it's not your grist

my $ is on mash temp
 
Those cheap turkey fryer thermometers are garbage. Originally, I was going to ask if you knew your water pH, but you say 7.6 which is about what mine is and pH has never been an issue for me. Then I read you are using the Turkey Fryer thermometer. Those things are garbage as it relates to mash temps. I put my money on mashing too high.

Please post your results
 
I'm certain it's the thermometer. Get a very accurate thermometer, and mash at 152, and you'll get FGs in the 1.010-1.016 area, depending on ingredients.
 
Summa *****, both my thermos were off by 10+ degrees. Now I have a crapload of sweet low abv beers. Grrr
 
You aren't first one it has happened to. It always sucks but at least you caught it.
 
Thanks everyone for the input. This site is by far the best out there for any info on home brewing and more. Cheers to better future brews!
 
I made my brew after fixing the thermo issue. Ended up getting ingredients for a 5 gallon batch when I was aming for three. Slight oversight when I scaled down a recipe that was for 10 gallons when I thought it was 5... I did end up with 1.090 and the next day found the airlock on the floor and a splatter on the ceiling o.0
 
Nice, I've had that happen before...would've been kind of fun to see it when it blew off.
 
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