Consistently High Final Gravity - A.G

[elmito]

My last 4, all grain batches have stopped fermenting at 1.020 and I need to figure out whats causing it.

Brews: Citra "SMASH," Milk Stout, Rye Pale Ale, Citra "SMASH"

At first I thought it was a fluke but since I brewed the same beer twice and hit the same exact O.G and F.G on both brews I think its safe to assume I'm doing something wrong.

Gonna try to run through all the data that I've collected and hopefully some of you amazing folks can chime in and help me out.

 

[Rbeckett]

Just out of curiosity, did you check your hydrometer in plain water? Mine was a tad off in plain water, when I remove the error in the zero setting my gravities all fall in the correct ranges, but my hydro reads high. Just a thought.

Bob

 

[opiate82]

This thread may be of interest to you: https://www.homebrewtalk.com/f36/controlling-attenuation-through-mash-times-60576/

 

[elmito]

Just out of curiosity, did you check your hydrometer in plain water? Mine was a tad off in plain water, when I remove the error in the zero setting my gravities all fall in the correct ranges, but my hydro reads high. Just a thought.

Bob

looks like my hydrometer is reading about 1-2 points high. I used tap water, I don't know if it that makes a difference. This is DEFINITELY a good start, thank you!

 

[elmito]

This thread may be of interest to you: https://www.homebrewtalk.com/f36/controlling-attenuation-through-mash-times-60576/

This is exactly why I love this forum so much.

I've never mashed for more than an hour. I will definitely try this on Thursday when I brew my Black IPA.

 

[hops2it]

I haven't checked out the recipes you listed but what method are you using for yeast addition? Packets? Hydrating or no? Starter or no?

If you're using packets on a higher than average grain bill, might want to consider adding 2 pks of yeast and rehydrating can really help getting things rolling as well.

Also, make sure there's nothing in your routine that involves moving the primary to cooler conditions after a certain period of time. Would also be of benefit to know how long you are running your primary.

 

[elmito]

The brewer at work said to check my mash temp as well. If I understood correctly, I might be extracting unfermentable sugars if I mash at too high of a temperature.

Here are my previous mash temps (these aren't exact but are accurate to a degree or two, no fancy temp controllers):

Citra v2 - 158*
Citra v1 - 158*
Rye Pale - 152*
Stout - 152*
Hibiscus Wheat - 155*

 

[elmito]

Hmmm, I just looked back at my notes, my Hibiscus Wheat went all the way down to 1.011 and that had a much longer mash time because of a stuck mash.

 

[hops2it]

All those mash temps look fine to me. And generally speaking, a 60 minute mash should give you the results you seek. That's a heck of a blanket statement but I'd stand by it in most situations. How long you mashing for in those instances?

 

[elmito]

I haven't checked out the recipes you listed but what method are you using for yeast addition? Packets? Hydrating or no? Starter or no?

If you're using packets on a higher than average grain bill, might want to consider adding 2 pks of yeast and rehydrating can really help getting things rolling as well.

Also, make sure there's nothing in your routine that involves moving the primary to cooler conditions after a certain period of time. Would also be of benefit to know how long you are running your primary.

Thanks for the input

For all 5 of my mentioned brews, I've made 1000mL yeast starters using either white labs liquid yeast or safale dry yeast. I built a PC Power Supply Stir Plate I found somewhere on these forums.

I brew 10 gallon batches and just now got my hands on a larger flask so will bump my Black IPA to a 2000mL yeast starter and give it another 24 hours to get going before the pitch.

The Citra Pale v2 was in the fermenter from 4/5/13 till 5/2/13 @ a consistent 68* at which point it had been stuck at 1.020 for at least 4 days of regular measuring. I figured fermentation was done. Transferred to secondary and dry hopped.

 

[elmito]

All those mash temps look fine to me. And generally speaking, a 60 minute mash should give you the results you seek. That's a heck of a blanket statement but I'd stand by it in most situations. How long you mashing for in those instances?

All brews had a 60M mash time with the exception of the Hibiscus Wheat which had an extra 30M added to mash time because it got stuck.

 

[hops2it]

I brew 10 gallon batches and just now got my hands on a larger flask so will bump my Black IPA to a 2000mL yeast starter and give it another 24 hours to get going before the pitch.

Appear to be on the right track there for your 10 gallon batches. I ran some similar numbers on a recent bock I made and came up with just north of a 2L starter (w/ stir plate).

 

[BeerMyLove]

Did you move them around just a bit to get the yeast to ferment the remaining sugars? Or at the very least get a few points lower.

 

[Yooper]

Those temps are pretty high, especially if they might be off "a degree or two".

I'd mash most beers at 151/152 if you want them to finish at 1.010-1.012. I mash my malty beers (like my Dead Guy clone and oatmeal stout) at 156 or so and they finish at 1.020.

 

[madira_maker]

I had the exact same issue and found my thermometer was off by ~12degF. So, I was really mashing at ~165 degF making unfermentable sugars.

Do a cold bath and boiling water test with the thermometer

 

[geneticbiscuit]

Given that we don't have all the details of your process, it would help to know how the final beer tastes. Is it overly sweet? If so there is an under-attenuation issue which could be due to a high percentage of unfermentables (mashing too high), poor yeast performance (under-oxygenating/not enough nutrient/too small starter), or both. If not, maybe you have a dough ball issue in your mash, which gets broken up when sparging (if you batch sparge) and extracts starches?

 

[gozer]

^ what madira_maker said. Check/calibrate your thermometer. Mash at 150F/66C and you should be good to go.

Mash temp was the problem in my case. Fixed with the last two batches and they came out nice and dry.