Expert help needed - Final gravity way too high!

[samwakeling]

Hi everyone,

I am a beginner brewer in Sydney and have had a few nice brews so far. My 5th batch was a BIAB using a 19L bigW pot. I was thinking I would be able to get 16L out of the pot, but hadn't accounted for the massive amount of trub from BIAB and ended up with about 12.5L...

I was trying a Sierra Nevada Pale Ale clone,

3484g Pale malt​

348g crystal malt​

​

14g Perle (7%) – 60 min​

4.5g magnum (10.5%) – 60 min​

28g cascade (4-7%) – 15min​

21g cascade (4-7%) – 0 min​

​

mash:​

- heat water to 72c, add grain​

- 60 mins @ 68c​

- add boiling water to have 25 min @76c​

- 90 minute boil​

- dunk sparged the grains In a litre or two of water, added this too the boil. ​

​

boil: ​

missed efficiency- gravity reading during boil (cooled) was 1.044, so I added 150grams of LME (dry) in the last few minutes of the boil. ​

​

cooled and pitched US-05, OG=1.054​

With the recipe I ended up with 10% crystal instead of 6% - a mistake revolving around my lack of understanding of pounds and ounces.

fermenting notes (fridge controlled by STC)​

7/11 (brewday) Aerated wort (shaking fermenter with tennis ball under base), Pitched that evening, next morning their was airlock activity. Holding at ~18c (ambient in headspace of fermenter)​

​

11/11 airlock activity stopped yesterday. Gravity is at 1.030. tastes very promising.​

​

16/11 still at 1.030 – swirled wort and have brought temp up to 19 degrees. It appears that fermentation is continuing at the higher temp.. also have a starter of US-05 going just incase.​

​

21/11 – even though there was observable bubbles coming from the airlock (once every 3-5 min) the gravity is still at 1.030 5 days later! Pitching some more yeast and dry hopping! Ahhhh! Yeast is pitched, and bubbling away at a similar rate still.​

​

23/11 – Gravity =1.030 sigh.​

Troubleshooting thus far:
- pitched plenty of yeast (as according to beersmith.), grew a packet of US-05, in 1.8L starter with stirplate, then harvested a little bit before pitching.
- Evidence of this seems to be that the second pitch (which was built up in a 2L starter with stirplate) has had virtually no effect.


- One thing I do not understand is that between 16th and the 21st of November, the airlock had bubbles ever 3-5 mins, consistently, but no reduction in gravity was realised?

- Hydrometer reading wrong? I have looked at a few guides for using hydrometers. Tested it on water for calibration - which was almost perfect. And I spin it or bob it up and down to get rid of carbonation bubbles...

- Mash temps have led to an unfermentable wort? This is what I feel like the guilty culprit is currently. Has mashing 10% of crystal at 76 degrees fro 25 mins led to complex sugars which the yeast isn't breaking down?

- Aeration? Currently I just give the fermenter a shake with a tennis ball underneath it to aerate the wort before pitching. Apparently this is not really effective. But would it be responsible for this stuck fermentation?


Any help or guidance with this is very much appreciated so thank you in advance

 

[boybrewer]

Have you checked the hydrometer in cool tap water . It should read 1.000 if not just adjust it by the amount it is over or under .Sorry just read the rest of your post . You seem to have done everything right , I don't think that the crystal would have much effect . Maybe add one or two pts to the final gravity but not 15 or so .Your mash temp looks ok next time I would mash at around 66 - 67 * C , maybe your thermometer is out , have you checked it against another trusted thermometer and checked it in boiling water and ice water ? Don't rely on the air lock activity trust the hydrometer . RDHAHB and be patient leave for it for a few more days then check it.

 

[samwakeling]

Hey beer belly,

Yea I have done that - its almost spot on.

 

[slcmorro]

Crystal attributes a lot of non-fermentable sugars to your brew. 10% is quite a lot.

When I plug in your stats to BrewMate as 12.5L finished volume with 70% efficiency, it returns OG of 1066 and FG of 1020. 68c makes a full bodied, less fermentable beer so 1030 or there abouts seems relatively on par, considering what you've stated above. I'd expect maybe 1025ish, but those few final grav points can sometimes be stubborn.

The airlock really is no indicator of anything useful. After you dry hopped, you may have displaced more CO2 that was in solution, so the airlock kept bubbling away. The barometric pressure differences inside and outside the fermenter could have had a part to play... my point is, they're not a clear indicator in any case.

All you can really do at this stage, is notch the temp up to 22c (won't hurt it now it's mostly fermented) and give the fermenter a swirl. Should see a few more points drop off perhaps.

In the end, you've made beer.

 

[samwakeling]

Hey mate,

Yes, I feared that would be the answer and really hope its not too sweet!

When I plug it into Beersmith2 @60% efficiency it get OG1.060 and @70% efficiency 1.069, with FG's of 1.015 ad 1.017 respectively.

I really like your point about the barometric air pressure - haha I open the door of the fridge, the gases outside the fermenter change, i see bubbles - I jump for joy - haha laughing at myself right now!

I'll bump up that temperature and see what happens!

Cheers

 

[slcmorro]

Best of luck buddy. In the end it won't matter. You'll still have beer to drink

 

[Hippy]

Two things come to mind which could be the cause of your problems.
Firstly, it's not advisable to make a starter for dry yeast as a starter of the sizes you have used would probably do more harm than good to the health of the yeast cells.You are better off just rehydrating before you pitch. Based on the amount of wort you're fermenting however and the fact you repitched, I doubt that's the issue.
More likely, if your thermometer is innaccurate by a couple of degrees you may have ended up with a shitload more unfermentable sugars than you expected.
Try calibrating your thermometer to get an idea if your mash temps were accurate.
If this is the case a good solution would be to brew the recipe again aiming for a much drier beer with less body than what you want and blend the two.

 

[MaltyHops]

Unless you're going to keg the beer, it might be worth doing a fast ferment test to try and figure where the beer is going to get to.

My beer is 1022; Can I bottle it?

Stalled Ferment At 1030

 

[samwakeling]

Hippy, I think you have nailed it. I just got a some tap water to a rolling boil - (139m above sea level which should boil around 100c) and it only got to about 94-95c with the candy thermometer I have been using!

Sounds like a new thermometer has just gone to the top of the shopping list!

Blending is also a good suggestion - i'll get researching!

Cheers mate, very much appreciated!

 

[buckerooni]

from time to time thermapens are discounted: http://www.ebay.com.au/itm/291287642846?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

mine cost me $AUD 65 to my door