Hey guys, back with another issue. Recently brewed a red ale. Had a stuck mash as recirculation was poor and had to stir often. Will fix this by taking some water from sparge and adding to mash instead or by adding some hulls. Due to this my temp during mash kept moving between 64c (147f) to 67c (153f). OG was 1.042 and FG finished at 1.005. Was aiming for 1.010. Yeast i used was wyeast 1335 (1.2 L starter due to the yeast age). 73-76% attenuation expected, got 87% … when tasting samples I could not taste or smell any off flavours, tasted lovely actually. Checked my hydrometer also in distilled water and shows 0.099. Do you think it could be the mash temperature ? Or what could it be ?
FG lower 5 points than expected
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The sugars you created during the mash because of the particular temperature you chose or how well you where able to hold that. Did the recipe specify a temperature to hold for mash or did you do your own thing?
A infection maybe. Wild yeasts will chew on more of the sugars that we consider unfermentable.
Probably a few other things that might have been. I wouldn't worry much if it tastes good enough. 2 points I feel is nothing, but 5 points you might at least try to figure out what possibly made go that low. Is this the only time you ever brewed this particular recipe?
You are sure that was the actual final gravity and it wasn't on it's way to a lower number didn't you?
A infection maybe. Wild yeasts will chew on more of the sugars that we consider unfermentable.
Probably a few other things that might have been. I wouldn't worry much if it tastes good enough. 2 points I feel is nothing, but 5 points you might at least try to figure out what possibly made go that low. Is this the only time you ever brewed this particular recipe?
You are sure that was the actual final gravity and it wasn't on it's way to a lower number didn't you?
67c for 60 min is what it asked for but as I said, temp kept changing between 64 to 67 unfortunately.
Since this is not the first time i ended up with gravity 3-5 points lower than expected (happened for all my 6 brews actually) I also assumed it might be an infection and hence anything that doesnt get boiled I changed for new equipment as there were smal tiny scratches in my bucket which i now use only as sanitising bucket during brew day. I also cleaned everything again with pbw. Except the scratches I would consider myself extremely careful with sanitasion so I started ruling out the infection. Also all the beers actually tasted fine.
Yes, first time brewing this, kept it quite simple actually
87.5% maris otter
7.5% crystal 60L
2.5% munich
2.5% roasted barley
30g east kent goldings
Some small water additions like calcium chloride, epsom and gypsum.
I noticed that my all in one system shows temp 2c higher than the actual mash temp only on this brew day though so when going for light bodied beers i might have been brewing with temps of 61c even instead of 64c.
I hope it wasnt going any lower, day 6 fg was 1.006 and day 10 it was 1.005 so i racked to secondary off the yeast cake (first time using secondary).
Im just wondering could the mash temp really cause 5 gravity points difference ? Does mash ph have anythingto do with it or is that to do only with mash efficiency and hitting og ?
Mashing at lower temps will give you more fermentable sugars. I bet that's a big part of the cause, but something else may be playing part. I don't think that lower temps will cause that big of discrepancy. What temp did you ferment at?
Temp fermented fridge to 19.5 so inside the fermenter it might be around 20c ? recommended for this yeast is 17 - 24c. I just moved my recipe from Brewfather to Beersmith, inputed that mash temp was around 63-64c and estimated FG was 1.006 where as changing mash temp on brewfather still shows 1.010 as estimate. I guess it could have been the mash temp in the end ?
I vote for inconsistent mash temperatures. Also, keep in mind that gravity numbers published by a recipe are estimates and not absolutes. If you hit the numbers that's great but there is nothing wrong if you don't. That said, a massive difference could mean problems but I wouldn't worry about a 5 point difference. We don't brew numbers, we brew beer.
Thanks for the input ! As i mentioned above i didnt realise that the top of mash is 2-3c lower than the bottom where the temp probe is meaning that some brews I mashed as low as 63c ! I seen a brulosophy experiment on low mash and they too got as low as 1.004 when mashing at 64c. Again i do doubt its an infection as i replaced most of the cold side (buckets, tubing etc.), boiled everything, soaked in pbw, rinsed and sanitise multiple times during brew day. Its just my perfectionist side would love to get at least 2 points within the expected FG. 1.005 for red ale is outside of the style range is what irritates me.
Improvement is good. You've already gotten better info about your actual mash temperature and gradient. Maybe you can find a way to prevent the "stuck" mash that affected temperature stability. This is also improve temperature uniformity within the mash.
Sounds like you're making good beer and just need to tweak things to make it even better!
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There is always the possibility that you have something that you aren't cleaning and sanitizing well. Ball valves and spigots are some of the biggies. Even if you soaked them all day, gunk can be hidden and never get touched by sanitizer that will be when you open and close them to let your wort though.
For things used prior to and during the boils, those aren't a issue. Heat of the boil itself and the time involved take care of that. But things you use during cooling and fermentation are where you should look.
If your FG is only five points off, I still might believe mash temps or some other unknown, but if your SG actually goes lower, I'd be looking for something not getting cleaned and sanitized properly or some other source of wild yeast and microbes getting in.
Maybe even your breath if you stick your nose in to breath the wonderful smells.
For things used prior to and during the boils, those aren't a issue. Heat of the boil itself and the time involved take care of that. But things you use during cooling and fermentation are where you should look.
If your FG is only five points off, I still might believe mash temps or some other unknown, but if your SG actually goes lower, I'd be looking for something not getting cleaned and sanitized properly or some other source of wild yeast and microbes getting in.
Maybe even your breath if you stick your nose in to breath the wonderful smells.
Have you previously brewed using a diastatic strain of yeast, e.g., Saison? If remnants of that strain get in your new batch it can attenuate it much lower.
Thanks ! Im going to start by increasing my mash volume by around half a gallon and maybe adding some rice hulls. Hope that helps.
I hope notThere is always the possibility that you have something that you aren't cleaning and sanitizing well. Ball valves and spigots are some of the biggies. Even if you soaked them all day, gunk can be hidden and never get touched by sanitizer that will be when you open and close them to let your wort though.
For things used prior to and during the boils, those aren't a issue. Heat of the boil itself and the time involved take care of that. But things you use during cooling and fermentation are where you should look.
If your FG is only five points off, I still might believe mash temps or some other unknown, but if your SG actually goes lower, I'd be looking for something not getting cleaned and sanitized properly or some other source of wild yeast and microbes getting in.
Maybe even your breath if you stick your nose in to breath the wonderful smells.
! Again though, the chiller gets boiled, tubing to and from chiller dont touch the wort but are sanitised either way in boiling water and sanitiser as you can never be too careful. I rack to fermenting bucket using recirculation arm that runs during last 15 min of boil to get sanitised (tubing again also boiled and sanitised). Fermenter sanitised plus its new first batch in it. New airlock. Thereferoce everything on the cold side should be fairly clean and new.I did make a saison once in my old bucket though which now i only use as sanitising bucket during brew day.
Doubtful that would cross over.
More likely mash temps or infection, as others have suggested.
Interesting. I use Brewfather too. I’m gonna have to try that out, see if changing mash temps changes the FG estimate.
As far as fermentation temp, sounds like that’s not the issue. You’d also have plenty of off flavors too. I’m guessing it’s the mash temp that got you where you are.
redrocker652002
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I am in no way a pro at this, and I use Brewfather as well. What I noticed, and I have no idea if this is anything to add to your list, is when I input the fermentables the L number on Brewfather sometimes does not match the L number on the bag of grain. Also, when I was first trying to dial things in, my efficiency percentage was off so my OG and FG were off to what I was getting at brew time. Could it be one of those things? Just throwing it out there, but like I said, I am in no way even a novice. LOL.
It does change if you play around with temperatures in the normal range but then you can go for example as low as ypu want and it stays the same where as beersmith takes every celsius into consideration. I might start using beersmith just for fg prediction.
Thanks for the input ! With the L do you mean the Lovibond ? If so I dont think it should affect much other than the potential color of the beer but i might be wrong. Efficiency should be ok for me, i usually get 73-75% hitting the OG. My solution for next batch will be to increasy my system by 2c during mash to make sure the top of mash is at the correct temp. Ill also change my grain/water to ratio to 3.2l per kg as i did 2.7 up until now. This should avoid stuck recirculation during mash making sure temp is stable and not dropping by 2-3c during mash.
