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Final Gravity


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#1 snickle09

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Posted 20 March 2017 - 04:51 PM

I've made a few all grain batches (pale ale, pacific ale, IPA, IIPA and a porter) and can't seem to reach the final gravity target. All recipes I've used have said a final gravity of 1.010 and all of mine have come out at between 1.024 and 1.018. All beers so far have tasted good and I'm happy with the results as I'm only new to brewing but am just wondering how I get down to those final numbers? I've only used safale US-05 dry ale yeast at a temperature of 18.5C which is controlled. And I've let each batch sit in the fermenter for 2 weeks each. I used 2 packs of yeast in the IPA and the IIPA too.

Is there something else I should be doing to get to my target? Thanks in advance.

Edited by snickle09, 20 March 2017 - 04:51 PM.


#2 manticle

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Posted 20 March 2017 - 04:53 PM

Are you measuring gravity with a refractometer?



#3 snickle09

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Posted 20 March 2017 - 04:57 PM

I use it but I don't believe it works as I get random inconsistent readings. I go off of my hydrometer which is always consistent.

#4 manticle

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Posted 20 March 2017 - 05:02 PM

If using a refractometer after fermentation has started, you need to correct for the presence of alcohol using a conversion chart or software.

 

If you are getting those readings with a hydrometer and you trust the hydro (reads 1.000 in 15-20 degree water?), then something is probably not right. To determine that though, we'd need more information about recipes - original gravity, mash temperature and time, grist used, yeast amounts, aeration techniques, rehydration techniques, yeast date, etc.

 

If yeast is old or in insufficient numbers, that can lead to high finishing gravity. If mash temp is high or mash time too short, that can also.

High gravity/ alcohol beers need more love (mostly yeast that's up to the task), lack of oxygen or too many simple sugars can lead to yeast stalling or slowing, high amounts of roast grain can give higher finishing gravity, etc.

 

So many variables so if you're using the hydro correctly and it's OK, let's get some more info.



#5 BEERHOG

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Posted 20 March 2017 - 07:25 PM

what temp are you mashing at and have you calibrated the thermometer you use to measure?  



#6 Danscraftbeer

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Posted 20 March 2017 - 07:46 PM

Combination of events. I'd think.

Mash temps too high?

Yeast counts too low?

Oxygenation pre ferment too low?



#7 snickle09

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Posted 20 March 2017 - 07:58 PM

Cheers for the response manticle and Beer hog. The latest batch for the IIPA included 4.68kg of ale (BB-Au), 200g of medium crystal and 160g of Cara Pils for the malt. Mashed at 66 degrees for an hour and mash out at 77 degrees for 10. Then a 90 minute boil with a range of hops at different times (centennial, simcoe, warrior, Amarillo, chinook and Columbus). The knockout was 11 litres and the OG was 1.088. I fermented for 7 days at 18.5 degress and then another 8 days at 21.5 degrees. Used 2 lots of the Safale US-05 Ale dry yeast and they were in the fridge at 18.5 degrees prior to pitching but were straight from the pack and I don't know about use by dates on them.

Also I haven't yet done any aeration or rehydration techniques as I'm only new to this and am learning as I go. And Beerhog, I am currently using a grain father connect to brew and I checked the temps of it the first time I brewed with a digital thermometer and they were almost identified for a range of temps (only out by less than 0.5 degrees).

#8 snickle09

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Posted 20 March 2017 - 08:00 PM

Not sure danscraftbeer. I'm hoping the mash temps are ok as I'd like to think the grainfather was worth the price. But the oxygen pre ferment is above me at this stage.

#9 Danscraftbeer

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Posted 20 March 2017 - 08:12 PM

If you have around 1/3rd headspace in your fermenter with your brew then you can seal it and shake it well to oxygenate it.

Long boil takes out all the oxygen and your yeast needs it at the start. I pitched the yeast then did the seal shake. Some shake then add the yeast etc.

Some experts have said that shaking it for 45 seconds is enough but I used to shake it for 4 minutes. Nothing wrong with a bit of exercise.

 

As long as you do it sensibly, not back breaking etc. I did it with 40lt brews in a 60lt plastic fermenter. Seal it (I used short piece of 10mm stainless steel rod fit perfect in the grommet of a plastic fermenter)

Gently tip it on its side and roll it back and forward. Watch it froth up. That's a good thing...


Edited by Danscraftbeer, 20 March 2017 - 08:17 PM.


#10 snickle09

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Posted 20 March 2017 - 08:17 PM

I used the plastic fermenters. And yeh, there is always head space in them. I'll give that a try next time. Cheers Dan.

#11 2cranky

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Posted 20 March 2017 - 09:03 PM

Hey Snickle,
Your OG of 1.088 is very high. What was your target OG?
If you are trying for 1.010 you get ABV10.4%☠️☠️☠️☠️

#12 Danscraftbeer

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Posted 20 March 2017 - 09:24 PM

Hey Snickle,
Your OG of 1.088 is very high. What was your target OG?
If you are trying for 1.010 you get ABV10.4%☠️☠️☠️☠️

Yes. I missed that. That's not newbie brewing. That's above intermediate levels. Harder to drink, harder to achieve. 

Try OG around 1.040 to 1.060. That itself is a very broad range of good beer if you aim to get FG =  around 1.010.

That is my realm. :chug:



#13 snickle09

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Posted 21 March 2017 - 05:20 AM

Hey Snickle,
Your OG of 1.088 is very high. What was your target OG?
If you are trying for 1.010 you get ABV10.4%☠️☠️☠️☠️


It was meant to be 1.086. Based off of a Pliny the younger recipe. Scaled it all down from a 5 gallon batch to fill a 9 litre keg. So yeh, it was meant to be around 10.2% or so. Having said that, the other beers I've brewed which have been weaker have finished with similar gravitates. From 1.024-1.018. Can't quite get to 1.010.

#14 manticle

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Posted 21 March 2017 - 06:32 AM

You'll need to go through your process steps one by one and eliminate variables.

First, test your hydrometer, thermometer and fermentation control. Assume nothing is correct, check and double check everything.
Then take a simple recipe - pale plus maybe 5% crystal to 1040 -1050, hopped to 35-50 ibu.

Fresh yeast - look at rehydrating according to manufacturers instructions.

Aerate well.

Once that's dialled in, play with high octane stuff.

My money is on something being out.

#15 snickle09

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Posted 21 March 2017 - 07:08 AM

Cheers manticle. I'll do that and see how I go. Appreciate the advise. Cheers.

#16 RobW

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Posted 21 March 2017 - 11:40 AM

The attenuation of that yeast is around 75% so you will struggle to get you FG below 1.020



#17 Dae Tripper

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Posted 21 March 2017 - 02:10 PM

I used a spoon to aerate previously, but now I have a small stainless mash paddle with a handle that fits into my battery drill or I empty my cubes from a hight with this from Keg King which is possibly the best $9 I have ever spent.Attached File  ret5356_tap_in_cap.jpg   2.29KB   6 downloads

#18 snickle09

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Posted 21 March 2017 - 08:23 PM

The attenuation of that yeast is around 75% so you will struggle to get you FG below 1.020


What yeast do you recommend that would get there?

#19 manticle

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Posted 21 March 2017 - 09:04 PM

1388 will get there but there are flavours associated that might be inappropriate.
Gigayeast have an ipa yeast.

Basically look at attenuation percentage and alcohol tolerance of any appropriate style yeast and select based on that. Easy enough figures to find.

#20 2cranky

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Posted 21 March 2017 - 09:16 PM

Whack it through a stil?