Stiring The Mash?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
crackhead7

crackhead7

Well-Known Member
Joined
Apr 18, 2010
Messages
233
Reaction score
1
Location
cleveland
I have not been all grain brewing for very long. I have been consistently getting beers that attenuate further then i have planned. ie. 1.010 vs 1.012 or 1.012 vs 1.014. It is always the a .002 difference. I use a 10gal beverage cooler from HD. I do ten gallon batches and that pretty much fills the tun. I have tested my thermomter and it is calibrated correctly. I sometimes have to mash at a lower grist ratio to accommodate the size of the mash usually I end up in the range of 1.2 - 1.5 qts/lb. I have a suspicion that there might be a tempature stratification happening within the tun during the mash causing the bottom of the mash to become more fermentable? My thought was to stir the mash at 30 mins, but till now I have been scared to open the tun and letting heat out. However it might just be easier to initially set a higher mash tempture. I have been mashing at 152* I know that there are alot of other variables that could be casuing this such as yeast health / strain, different malts etc. I have had this happen using Dry Nottingham, Wyeast 1332, WLP051, and WLP 400. I use mr. malty to get a ballpark on pitching rates but usually end up underpitching the recommendation. I base this on the fact that my ending starter volumes are usually 300-400 ml less the suggested. I know it might be helpful to have the recipies i put two of them here https://www.homebrewtalk.com/f36/my-last-brewday-285332/

Any thoughts and or suggestions would be appreciated as I try to work this out.
 
First off, I would personally love to only be .002 off of my anticipated FG!

Maybe on your next batch, add in a few more ounces of grain to try to add some unfermentable sugars.

Also, I wouldn't be afraid to open the mash tun to check the temperature as long as you have some really hot (near boiling even) water handy to throw in if it's a little under temp.

Also, are you heating up the mash tun before you add the grain?
 
Just raising your temperature a degree or so should do the trick. I have one question though, how are you measuring your final gravity? If you are using a refractometer then a gentleman named Sean Terrill did some experiments on the Basic Brewing podcast that showed he consistently got lower than actual readings with his refractometer using the standard correction sheet. He developed a corrected formula based on his results. You can google it if you are using a refractometer. If not, than I'd just tweak your mash temp up a bit to correct you FG.
 
I don't know about others but I see almost .002 error factor in just reading my hydrometer. I have to take my best guess whether it reads 1.010 or 1.012???
Maybe I need the FG type hydrometer.

Question, why are you intentionally underpitching?
 
I don't heat the tun I set my strike water at the temp beer smith tells me to and I usually nail it right on the head. I spend the first 5-10 mins making sure that I have the right ph and adjust as necessary. I know .002 isn't much but they are just ending up a little dryer then i would like. I know there are easy fixes such as you suggested adding a llittle more crystal or other malt high in unfermentables, and mashing at a higher tempature but I really want to know what what I am missing as I develop a good iunderstanding of the whole process. Maybe I am just over thinking the whole thing. I also thought that maybe since i haven't entered the exact spec for the malts that I use into beer smith that the batch of malt i am using has more extract potential. I have been shooting for 70% eff, but have been getting a higher eff. with higher OGs then expected.
 
I'd experiment mashing a little higher. I was getting great attenuation from the Edinburgh strain that I use often, and adjusted the mash temperature up three degrees and was pleased with the results.
 
i've never had a problem with the out comes of my pitch rates when making a starter. i use 2000ml flask that i make 1600-1800ml staters in. One for each 5 gal fermenter. Usally Mr. Malty wants a 1.5 -2 qt starter so it was my thought that 150-200 ml per 5gals less of starter isn't huge difference, but maybe I need to revisit that.
 
MaxSpang said:
First off, I would personally love to only be .002 off of my anticipated FG!

Maybe on your next batch, add in a few more ounces of grain to try to add some unfermentable sugars.

Also, I wouldn't be afraid to open the mash tun to check the temperature as long as you have some really hot (near boiling even) water handy to throw in if it's a little under temp.

Also, are you heating up the mash tun before you add the grain?
Click to expand...

PAPPERS this is what I was planning on doing for up coming batches of light beers as suggested by MaxSpnag also, I also thought about bumping my crystal percentages in recipies that call for it. I like many others have become obsessed with this hobbie and just wanted to understand the why of what was happening

Zen_Brew said:
Just raising your temperature a degree or so should do the trick. I have one question though, how are you measuring your final gravity? If you are using a refractometer then a gentleman named Sean Terrill did some experiments on the Basic Brewing podcast that showed he consistently got lower than actual readings with his refractometer using the standard correction sheet. He developed a corrected formula based on his results. You can google it if you are using a refractometer. If not, than I'd just tweak your mash temp up a bit to correct you FG.
Click to expand...

I have been using a hydrometer, but a refractometer is on the wish list. Maybe I should invest in a more sensitive (tighter range hydrometer) for checking final gravities, didn't think about it but it could just be a reading error on my part.
 
I'm willing to bet that you wouldn't be able to tell the difference between the two levels of attenuation - forget what the numbers say, how does it taste? Keep your process consistent, and make changes based on the sensory outcome. The actual numbers don't matter nearly as much as getting a working process does.
 
randomsample said:
I'm willing to bet that you wouldn't be able to tell the difference between the two levels of attenuation - forget what the numbers say, how does it taste? Keep your process consistent, and make changes based on the sensory outcome. The actual numbers don't matter nearly as much as getting a working process does.[/QUOTE

I would have to agree that a working process is essential. The beers taste fine but all are aging at the moment, so it will truly be evident in a few weeks what the outcome is.

Spartan1979 said:
Are you sure your hydrometer is accurate? Are you reading it @ 60?
Click to expand...

I chill and measure at 60* , I have yet to verify the accuracy of my hydrometer this thought hadn't occurred to me right off the bat, I'll do this this weekend when I get a chance to go get some distilled water.
Click to expand...
 
I don't percieve this as a problem I'm just wonder as to the why? But I agree it is important to make sure my Instruments are accurate to ensure that I am not on a wild goose chase to the why that might not exist. It is easy enough to adjust the process in order to achieve the desired outcome and I will do so if I find after aging that the beers lack body or are not at the residual sweetness level I desired. I appreciate all the feedback!
 
crackhead7 said:
i've never had a problem with the out comes of my pitch rates when making a starter. i use 2000ml flask that i make 1600-1800ml staters in. One for each 5 gal fermenter. Usally Mr. Malty wants a 1.5 -2 qt starter so it was my thought that 150-200 ml per 5gals less of starter isn't huge difference, but maybe I need to revisit that.
Click to expand...

Hmm, when I make a starter any bigger than 1200ml in a 2L flask I get overflow. How do you do 1800ml in 2L? No Krausen?
 
kh54s10 said:
I don't know about others but I see almost .002 error factor in just reading my hydrometer. I have to take my best guess whether it reads 1.010 or 1.012???
Maybe I need the FG type hydrometer.
Click to expand...

As much as we like to think it is, homebrewing is not an exact science. I know my hydrometer does not accurately read to .002 precision - the miniscus is more than .002 tall. When I got my refractometer, i stopped using the hydrometer and just measure to the nearest brix. I also know I can't accurately measure my mash temp. I frequently stir but if I move the thermometer around it will vary a few degrees C.

My beers have been finishing higher than expected recently (often greater than 0.005 more than expected)...I don't know the exact reason but today I mashed around 65C and threw a half pound of dextrose in the boil to see if that helps.
 
I agree with the others that .002 fluctuation is no big deal. There are so many factors like pH, yeast count and health, temperature, flocculation etc that are affecting the FG. A .002 difference is not even detectable by most folks. Heck, even breweries experience a .002 fluctuation!
 
Cromwell said:
Hmm, when I make a starter any bigger than 1200ml in a 2L flask I get overflow. How do you do 1800ml in 2L? No Krausen?
Click to expand...

The head space that i need in a starter depends on the yeast that I am using. The yeast that tend to have bigger kreusens i make smaller volumes to ensure no over flow those that tend to have little/no krausen I can make a bigger volume, this is why my pitch rates / stater volumes very. i recently had a starter overflow with wlp400

gbx said:
As much as we like to think it is, homebrewing is not an exact science. I know my hydrometer does not accurately read to .002 precision - the miniscus is more than .002 tall. When I got my refractometer, i stopped using the hydrometer and just measure to the nearest brix. I also know I can't accurately measure my mash temp. I frequently stir but if I move the thermometer around it will vary a few degrees C.

My beers have been finishing higher than expected recently (often greater than 0.005 more than expected)...I don't know the exact reason but today I mashed around 65C and threw a half pound of dextrose in the boil to see if that helps.
Click to expand...

zendog said:
I agree with the others that .002 fluctuation is no big deal. There are so many factors like pH, yeast count and health, temperature, flocculation etc that are affecting the FG. A .002 difference is not even detectable by most folks. Heck, even breweries experience a .002 fluctuation!
Click to expand...

i see the concensus is that .002 is miniscule, I now see that I have been getting good consistent results and should be enjoying that fact! Now that I have gotten this feedback form everyone here I'm am actually feeling quite pleased about my recent results.


Regardless I still am wondering what peoples' opinions are about stirring the mash after setting ph and temp. Would it provide any benefit to stir it half way through or should one leave it well enough alone and let it run its course undisturbed?
 
crackhead7 said:
Regardless I still am wondering what peoples' opinions are about stirring the mash after setting ph and temp. Would it provide any benefit to stir it half way through or should one leave it well enough alone and let it run its course undisturbed?
Click to expand...

I stir a few times during the mash just to even out the temp - the top and sides are always lose temp faster and are a few degrees lower than the centre. If you look in How To Brew, pg 203 "Your First All-Grain Batch" point 6 - "Stir the mash every 15-20 minutes to prevent cold spots and help ensure a uniform conversion". If your setup doesn't have wildly varying temperatures like mine, I'd just leave it and have another beer.
 
Haven't had many issues but I might just stir once at 30 mine, just in the summer here in norteasr Ohio it is currently quite cold.
 

Similar threads

SRJHops
Mash Thickness and Efficiency
2 3 4
Replies
140
Views
7K
doug293cz
doug293cz
U
Efficiency, decoction mash versus single infusion?
2 3
Replies
95
Views
4K
VikeMan
VikeMan
hilljack13
OG/SG very low
Replies
19
Views
672
hilljack13
hilljack13
I
SS Brewtech InfuSSion Mash Tun Custom Heater
Replies
7
Views
849
Indian_villager
I
G
Long time batch sparger, switching to fly sparging, need some tips
Replies
30
Views
3K
dmaxweb
dmaxweb

Latest posts

Back
Top