FG variations

[deeJay]

Hi all,
I do no chill double batches, 23L into plastic cubes x 2.
Recently I have been getting big variations on final gravity from the same batch, mostly over attenuating, same temps and yeast, (Verdant ipa) same fermentation time (7-8 days) same amount of dry hops. (usually 150g)
Example, Cube 1 might be 1.011 and cube 2 =1.008.
I use a tilt hydrometer and temp controlled fridge.
My recipe's usually call for 1.012 FG, I used to hit my numbers bang on or within a point all the time and now for some reason every batch varies and my beers range from 5.1% to 5.6%, most brews come out around 1.008 -1.009.
The only thing I can think of is that I used to dry hop near the end of fermentation as opposed to now I ferment out and then dry hop ?
any ideas ??
cheers.

 

[Minbari]

Are you using the tilt to measure or something more reliable?

Tilts are great for trending, but not for accuracy.

 

[Zambi]

Like @Minbari suggests
Check with a hydrometer, don't count on the tilt

 

[Brew Cat]

its not that far off really
mash temperature can change or thermometer goes out
malt efficiency is an average it can change
milling differences
volume accuracy
yeast viability, pitch rate
so many variables it is really an unanswerable question

 

[Donoroto]

Tilts are not very accurate at the end of fermentation. Use a hydrometer.

The tilt is great for seeing a trend - e.g. no gravity change for 3 days. And different tilts have different ‘error’ characteristics.

 

[Bigbre04]

if you use a hydrometer be sure that you check the temp on the liquid. it needs to be close to the calibration temp for the hydrometer. alternatively if you have a local brewery that you are friendly with, they have much nicer hydrometers and would likely compare your readings to thiers. generally would need about 350ml to take the sample. might have to convert from plato to SG, but thats not a big deal.

 

[Dave Y]

Like @Minbari suggests
Check with a hydrometer, don't count on the tilt

Tilts are not very accurate at the end of fermentation. Use a hydrometer.

The tilt is great for seeing a trend - e.g. no gravity change for 3 days. And different tilts have different ‘error’ characteristics.

Are you using the tilt to measure or something more reliable?

Tilts are great for trending, but not for accuracy.

So, like any tool it can fail, need recalibration - just like an old school hydrometer, or can be misread, misintepreted, etc. My tilts are both within 0.001 of my old school hydrometer at the calibrated temp. YMMV ( your measurements may vary )

@Donoroto does have a point; they're individual tools and there can be some variance.

I do no chill double batches, 23L into plastic cubes x 2.

I use a tilt hydrometer and temp controlled fridge.

so, 2 cubes, one tilt?

The only thing I can think of is that I used to dry hop near the end of fermentation as opposed to now I ferment out and then dry hop ?
any ideas ??

You could be seeing hop creep. No, that's the oddball WC IPA drinker. https://www.beerandbrewing.com/the-causes-and-effects-hop-creep-and-how-to-prevent-it

I'd validate that you're actually seeing a variance in the beer gravity - double check like @Bigbre04 suggests. He dry hops starting right after high krausen, when it starts to diminish and I'm kind of in that camp too. It speeds up the process overall, your 'beer' doesn't sit at room temp for days on end waiting for a possible infection.

IF you do have a variance, hop creep is a possibility from what you describe. You've identified one known variable / change. Ask yourself if anything else has been updated in your processing, ingredients, cleaning, & sanitizing.

 

[Bigbre04]

So, like any tool it can fail, need recalibration - just like an old school hydrometer, or can be misread, misintepreted, etc. My tilts are both within 0.001 of my old school hydrometer at the calibrated temp. YMMV ( your measurements may vary )

@Donoroto does have a point; they're individual tools and there can be some variance.




so, 2 cubes, one tilt?

You could be seeing hop creep. No, that's the oddball WC IPA drinker. https://www.beerandbrewing.com/the-causes-and-effects-hop-creep-and-how-to-prevent-it

I'd validate that you're actually seeing a variance in the beer gravity - double check like @Bigbre04 suggests. He dry hops starting right after high krausen, when it starts to diminish and I'm kind of in that camp too. It speeds up the process overall, your 'beer' doesn't sit at room temp for days on end waiting for a possible infection.

IF you do have a variance, hop creep is a possibility from what you describe. You've identified one known variable / change. Ask yourself if anything else has been updated in your processing, ingredients, cleaning, & sanitizing.

when you dryhop is really dependent on what style of ipa you are making. Yeast type also makes a big difference as some do better at hop creep then others.

I dryhop my hazy ipas at day 2 because the Voss is already basically done fermentation by that point.

for west coast that you want to be clear, you should dryhop it at the end or very close to the end of fermentation to avoid most of the biotransformation and to help avoid hop creep.

hop type also matters as some are more prone to creep then others.

 

[Donoroto]

My tilts are both within 0.001 of my old school hydrometer at the calibrated temp.

Less a function of calibration, more one of krausen goop.

 

[Dave Y]

Less a function of calibration, more one of krausen goop.

Yeah, I forgot to mention that one.
Once in good while the tilt gets caked with .. stuff. It can cause erratic gravity readings sometimes.
Also, when you're fermenting a farmhouse or wheat beer with an active / violent fermentation, the tilt will bounce around and show a pretty wide variance in readings until things calm down a bit.

 

[deeJay]

Thanks for all the replies,

Are you using the tilt to measure or something more reliable?

Tilts are great for trending, but not for accuracy.

I use tilt to see only when it is stable for a few days then use Smart ref.

 

[deeJay]

Thanks for all the replies, I use a smart ref for accuracy and the tilt is there for temperature and to see when fermentation has stabilised.

 

[deeJay]

when you dryhop is really dependent on what style of ipa you are making. Yeast type also makes a big difference as some do better at hop creep then others.

I dryhop my hazy ipas at day 2 because the Voss is already basically done fermentation by that point.

for west coast that you want to be clear, you should dryhop it at the end or very close to the end of fermentation to avoid most of the biotransformation and to help avoid hop creep.

hop type also matters as some are more prone to creep then others.

Yeah was thinking more hop creep but I wouldn't think that's a lot of hops to cause hop creep I thought you had to have loads of hops for that to happen. I do dry hop at the end of fermentation, although definitely something causing secondary fermentation so probably hop creep.

 

[Zambi]

Thanks for all the replies,

I use tilt to see only when it is stable for a few days then use Smart ref.

What's smart ref?

 

[Minbari]

Thanks for all the replies,

I use tilt to see only when it is stable for a few days then use Smart ref.

Ok, good. Then as others have said a 3 point deviation isn't much. Differences in mash temp or yeast health could cause that

 

[Ward Chillington]

Don't sweat the numbers...Repeat the Pappazian Mantra....RDWHAHB

 

[west1m]

What's smart ref?

I had to look it up too
Fancy $300 electronic refractory meter.
Looks to be in Brix but the details in the add I saw make it look like it would also read SG.

 

[Brew Cat]

I had to look it up too
Fancy $300 electronic refractory meter.
Looks to be in Brix but the details in the add I saw make it look like it would also read SG.

For that price should do the calculations
Basically a refractometer
A refractometer is a cheap tool that everyone should have in their kit
It's not one or the other argument

 

[Megary]

A refractometer is a cheap tool that everyone should have in their kit

Not to be argumentative, but why would I need a refractometer if I have a hydrometer? If the argument is that a refractometer requires only a smidge of liquid, fine. But I brew 2.5 gallon batches and have no trouble accounting for two 8oz hydrometer samples. I’m not a gadget guy, and maybe that’s blasphemy as a homebrewer. But less equipment in my kit is better for me.

 

[Minbari]

I had to look it up too
Fancy $300 electronic refractory meter.
Looks to be in Brix but the details in the add I saw make it look like it would also read SG.

This is the one you want. Put in a sample and it tells you the gravity in any form you like, even when alcohol is present. Only requires about 50ml

https://a.co/d/03SaLYY8