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BOBTHEukBREWER

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My latest brew is a pale english style bitter made with maris otter hops and cascade hops only. OG was 1.058 and after just 5 days it has stabilised at 1.018 - mash temperature was 68 deg C (154.4 deg F). I expected a slightly lower FG, any thoughts?
 

MalFet

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Under-attenuation is perhaps the most common problem in brewing, especially AG brewing. You'll find approximately a million billion threads about it on here.

You've got 68% attenuation right now, which is low for some circumstances but acceptable for others. You're going to have to toss out more info than you're currently giving us. Yeast type? Fermentation temp? Type of mash? Past experiences with setup/recipe?
 
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BOBTHEukBREWER

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ok sorry for not giving more details, safale 08 yeast, hydrated and made into starter with small amount of brewing sugar, I do not measure fermentation temperature, the bucket is on the kitchen floor, I would guess around 16 degrees C. I add water at 75 deg C to the grain using 20 quarts to 12 lb grain, mash for 1 hour and confirm completion with iodine test. As I drain off the liquor I add another 2.5 gallons of water at 85 deg C, last runnings were 1.026 SG - I suppose I am thinking about mashing at higher temperatures producing more unfermentable sugars, my previous 3 beers had FG's of 1.015, 1.014, and 1.010
 

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As I think you realize now, mashing at higher temperatures gives a fuller body, with more long chain sugars being created (not fermentable) so the FG will be higher (hence the bigger body)... If you want a lower FG, mash lower... Just be sure that you don't mash too low, since that will make the brew not as you desire.

I'm planning on mashing in the 152-154F range for a brew I'm making tomorrow. Projected OG is 1.074, with an estimated FG of 1.020... I'd like to get it into the 1.015-1.018 range. But, even if it is around 1.020, it will still be good beer. :D

Where your brew is now, it sits at about 5.2% ABV... A respectable brew.

If you have the resources, try experimenting with different mash temperatures for the same recipe. Also try different mash times. I'm tending to go with 60-90 minute mash times, getting solid results... I also sparge for 10-15 minutes... Tomorrows brew might have a longer sparge time, I haven't decided just yet.
 
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BOBTHEukBREWER

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thanks Golddiggie - why extend the mash time if all starch is converted? I am out of my depth here.
 

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ok sorry for not giving more details, safale 08 yeast, hydrated and made into starter with small amount of brewing sugar, I do not measure fermentation temperature, the bucket is on the kitchen floor, I would guess around 16 degrees C. I add water at 75 deg C to the grain using 20 quarts to 12 lb grain, mash for 1 hour and confirm completion with iodine test. As I drain off the liquor I add another 2.5 gallons of water at 85 deg C, last runnings were 1.026 SG - I suppose I am thinking about mashing at higher temperatures producing more unfermentable sugars, my previous 3 beers had FG's of 1.015, 1.014, and 1.010
Safale 04 or 05 maybe? I'm not familiar with 08.

Typically, one shouldn't make a starter with dry yeast. Simple rehydration is sufficient.

Warmer temps would as you suggest get you lower attenuation generally, but I suspect that there are two possible factors.

1) 5 days in, your fermentation may very well just not be finished yet. Especially without temperature control, you may have just lost some activity temporarily due to subtle temperature changes.

2) If you're not controlling fermentation, you're bound to get some significant variation in your attenuation from batch to batch. 16C a nice and cool, but fluctuations can mess with your yeast. Try warming up a touch to see if it progresses at all.

All that said, 68% is not terribly far off from what I would expect, so you might just be finished.
 

Golddiggie

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thanks Golddiggie - why extend the mash time if all starch is converted? I am out of my depth here.
From my understanding (and I'm sure Revvy will correct me if I'm mistaken ;)) longer mash times won't do any harm. You'll get better extraction, possibly, from a 90 minute mash, than a 60 minute mash (or maybe it's the 45 minute mash)... It also means that the sparging has less work to do (from my understanding)...

It's pretty easy, for me, to hold temps in the correct range for the 60-90 minute time frame. Towards the end, I've lost about 4F in the mash, which is still pretty good. I'm also getting high 70's to low 80's for efficiencies. Also pretty solid results (means I can use a bit less grain)... I am using the BIAB method, which helps where I am (small 1 bedroom apartment, no real space to setup a full rig outside).

I would also recommend letting a brew sit on the yeast for 2-4 weeks before considering it at FG... Just five days isn't long enough to consider the SG a FG... Give it another week, or two... Compare readings at least 3 days apart. IF they are identical, across at least two readings, then you could be at your FG. Before you consider bottling the brew, taste the hydrometer sample... IF it is at a stable SG, and tastes 'right' then it can be bottled...
 
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BOBTHEukBREWER

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I define fermentation end as 2 days with the same refractometer reading AND very little surface activity AND the beer beginning to clear from the top. I bottle at this stage and store the bottles at 24 deg C for 7 days then to a cool room temperature. Apologies, safale 04, the blue packet. I disagree re starter, as around 1 in 20 of my starters don't start, so I bin it and open a new packet. I will not risk putting dead or bad yeast into my wort.
 

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I define fermentation end as 2 days with the same refractometer reading AND very little surface activity AND the beer beginning to clear from the top. I bottle at this stage and store the bottles at 24 deg C for 7 days then to a cool room temperature. Apologies, safale 04, the blue packet. I disagree re starter, as around 1 in 20 of my starters don't start, so I bin it and open a new packet. I will not risk putting dead or bad yeast into my wort.
By your own definition, there's no way in hell it could have 'finished' in just 5 days... A 3 day fermentation, assuming you took a reading then, and again at day 5, is way too young.

I don't even think about sampling a brew until it's at least two weeks in primary. There's more for the yeast to do than just make alcohol for you.

I do think that just a day between the readings isn't enough time. Unless you have an ultra accurate hydrometer/refractometer. Even then, it might take two full days to drop just one gravity point.

I'm working to set up a proper pipeline so that I can still have home brew to drink while the others are in process. I'll typically 'plan' on six weeks from grain to glass (for brews with an OG of under 1.060)... With an additional couple of weeks buffer if the brew is for an event. That way, none of my brews are rushed...

Being patient with your brew is very often well rewarded... I started an old ale on 12/20/10 that I'm planning to finally bottle up next weekend.
 
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BOBTHEukBREWER

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The beer has finished fermenting after 5 days, and so can be bottled. In the bottle it ferments a tiny bit more to develop pressure, this is natural conditioning on the yeast. I start to drink them after 4 weeks in bottle. A refractometer is a refractometer, and by the way I graph the readings which further confirms the sg will not fall (significantly) any further. I find no improvement in bottle after 6 weeks or so, but accept much stronger beers may improve over months.
 
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BOBTHEukBREWER

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Is "old school" a term used in USA? I see no point in holding beer for weeks in bulk then adding more yeast and sugars to ensure carbonation in bottle. In UK many good bottle conditioned beers from microbreweries are on sale. Some are nearly as good as my own beer.....
 

Sean

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It isn’t meant to be derogatory, the opposite actually. Just an old way of doing things; using intuition and experience instead of calculation and precise measurement.

"Some are nearly as good as my own beer.....";)
 

MalFet

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BOBTHEukBREWER said:
I define fermentation end as 2 days with the same refractometer reading AND very little surface activity AND the beer beginning to clear from the top. I bottle at this stage and store the bottles at 24 deg C for 7 days then to a cool room temperature. Apologies, safale 04, the blue packet. I disagree re starter, as around 1 in 20 of my starters don't start, so I bin it and open a new packet. I will not risk putting dead or bad yeast into my wort.
You can define fermentation however you want, but the yeast aren't concerned with semantics :D If there is sugar left for them to ferment, then they're perfectly capable of waking back up even if it looks like they've flocced out. If you've got no temperature control and a rigid time schedule, you are bound to get some inconsistency. Not to say you shouldn't be happy with your beer, but I think these things are a pretty good explanation of what you are seeing with this batch.

If 1 in 20 of your yeast packets are dead, you need a new supplier.

BOBTHEukBREWER said:
The beer has finished fermenting after 5 days, and so can be bottled. In the bottle it ferments a tiny bit more to develop pressure, this is natural conditioning on the yeast. I start to drink them after 4 weeks in bottle. A refractometer is a refractometer, and by the way I graph the readings which further confirms the sg will not fall (significantly) any further. I find no improvement in bottle after 6 weeks or so, but accept much stronger beers may improve over months.
They are done consuming sugars, perhaps, but they are not inactive. If you are happy with your beer don't let me change your mind, but it's over simplistic to say that things are done after five days.

Regarding mash time: Many beers will be harmed by a 90 minute mash because some of the enzymes (particularly alpha amylase) are still very much active even after the long chain starches have been converted. This may or may not be bad, but for consistency's sake you should keep doing what you are doing and keep your mash time consistent. A longer mash will not make for better or easier sparging.

Good luck! :mug:
 
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BOBTHEukBREWER

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If 1 in 20 of your yeast packets are dead, you need a new supplier. These are safale sachets with long dates on them, my supplier (of yeast, chemicals, equipment) is probably the best in the UK. I stand by my claim that 2 consecutive identical refractometer readings, lack of visible surface activity and the beer beginning to clear in the bucket is the time to bottle. Subtle changes continue for a while in the bottle.
"Some are nearly as good as my own beer....." Surely we all make beers often better than many commercial brews...
 

kanzimonson

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It sounds like you used an English strain - low attenuation and quick fermentation.

I support bottling early so long as you're confident the beer is done. When I was bottle conditioning I would let it sit in the fermentor longer just for maximum clarification. I hate the flavor of yeast.
 

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Sounds like you're confident in your techniques and happy with your beer. As long as that is the case no need to change anything.

If you are open to suggestions/techniques I would add that temp control in the mash and fermentation stages would help you control the beer you're looking to make better. May want to start tracking that and charting it to see what differences you're finding. That way you can adjust going forward to make even better beer. You'd also be able to see how different mash and fermentation temps are affecting your attenuation as well.

Regarding fermentation time and when it's ready to bottle I would personally recommend waiting a little longer. Gives the yeast some time to clean up after themselves which is important for flavor profile. When I began doing this I found a nice improvement in my beers going forward. I've slowly but surely moved to the other end of the spectrum. I wait at least 3 weeks before bottling (preferably 4) and then bottle condition at 70 degrees for at least 2 weeks prior to tasting (preferably 3). Bottom line is my beer is turning out better/cleaner.

We all have our opinions/techniques and that is what makes this hobby great. However, don't completely disregard other options. I've tweaked my process/opinions way too many times to count and hope I continue to do so as it's progressively moved my beers towards more consistency and better taste.

cp
 
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BOBTHEukBREWER

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CPooley 4 - I wait at least 3 weeks before bottling (preferably 4)
Do you add new yeast and/or priming sugar when you bottle. I sometimes get bottles a bit on the flat side with my technique....
 

CPooley4

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No, I don't add any new yeast. I do add priming sugar though. I have a yeast pitch calculator and bottle priming calculator that I use for both of these items. You can take a look at it if you'd like by downloading the link in my signature. It's free to download/use if you'd like.

I do pitch with more yeast than some brewers. Though I don't recall having an issue back when I was just pitching one packet and not paying attention to yeast pitch amounts either.
 
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BOBTHEukBREWER

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Thanks, friend. When I next bottle I will transfer one gallon to a demijohn and leave it at cool room temperature for 2 weeks before bottling and compare the two batches.
 

CPooley4

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No problem. Good luck and let me know how that experiment turns out as I'd be interested to hear.
 

MalFet

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BOBTHEukBREWER said:
If 1 in 20 of your yeast packets are dead, you need a new supplier. These are safale sachets with long dates on them, my supplier (of yeast, chemicals, equipment) is probably the best in the UK. I stand by my claim that 2 consecutive identical refractometer readings, lack of visible surface activity and the beer beginning to clear in the bucket is the time to bottle. Subtle changes continue for a while in the bottle.
"Some are nearly as good as my own beer....." Surely we all make beers often better than many commercial brews...
I don't mean to suggest great milds can't be ready to bottle in 5 days. I do it all the time. But, that's why I'm confused..I assume the reason you are here is that you've got a degree of attenuation that you are not happy with. Maybe I am misreading you, but you seem resistant to any of the things that might fix it. Yeast can go dormant and then be woken back up. I don't think this is disputable. If your yeast are going dormant earlier than you want them to, why not try to fix it? This may or may not be the problem in your case, but it's a darn good place to start troubleshooting.

I'm not trying to argue the yeast point with you. If you've happy with 5% failure rate, more power to you. I wouldn't be and have never needed to be, but if you don't see it as a problem then it is not one.

Sounds like you are pretty happy with your methods and your results. There's no reason that you shouldn't be. But, if that's the case, I am not sure what you are asking for help about. In any case, brew on, brother man. :mug:
 
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