Final Og Lower Than Og Into Boiler

[Screwtop]

Before the boil...........................measure the volume and stir/mix the wort well..............then take sample for preboil gravity reading, remember temp adjustments.

After the boil...........................measure the volume, allow for wort expansion, calculate boiloff volume, calculate postboil gravity using the preboil volume and boiloff volume using a Calculator or Beersmith

Then...........................stir/mix the wort well..............then take sample for postboil gravity/OG, remember temp adjustments.

Cheers,

Screwy

 

[NeilArge]

Two different hydrometers would definitely be a potential cause, it would be good to know if they read differently or not. It's not that hard for the piece of paper to slip up or down inside that glass tube.

So, I tested both hydrometers in 20C water and both measured it at 1.000. The only thing I can think of now is that, as per QLDKev's advice (if I understand it correctly) there was too many suspended solids to provide a reliable reading in the pre-boil sample. I did get a bit of grain under the false bottom that made its way in to the boiler (I scooped it out before starting the boil) and maybe that made it worse?

Anyway, I have greatly appreciated all of the advice and help offered on this topic. I luv youse all
... in a brewer to brewer kind of way!

Best

ToG

 

[NeilArge]

Before the boil...........................measure the volume and stir/mix the wort well..............then take sample for preboil gravity reading, remember temp adjustments.

After the boil...........................measure the volume, allow for wort expansion, calculate boiloff volume, calculate postboil gravity using the preboil volume and boiloff volume using a Calculator or Beersmith

Then...........................stir/mix the wort well..............then take sample for postboil gravity/OG, remember temp adjustments.

Cheers,

Screwy

Ta very much Screwy. That sounds a great deal more rigorous approach than I have used thus far.

Best,

ToG

 

[smudge]

What I find interesting about this thread, is that some posters prior to the 14th post, assumed that Tunofgrunt was using a
refractometer...... talking Brix, undissolved solids etc.

Has our hobby come this far? Every man and his dog has a refrac? Mmmm....I do, and all of the brewers I know do too.

I reckon that soon we'll be quoting Plato instead of SG in the recipe database. The techology gap between professional
brewers and the great unwashed is narrowing.

Not that this is a bad thing. Just interesting.

Cheers,
smudge

 

[AndrewQLD]

What I find interesting about this thread, is that every poster prior to the 14th post, assumed that Tunofgrunt was using a
refractometer...... talking Brix, undissolved solids etc.

Has our hobby come this far? Every man and his dog has a refrac? Mmmm....I do, and all of the brewers I know do too.

I reckon that soon we'll be quoting Plato instead of SG in the recipe database. The techology gap between professional
brewers and the great unwashed is narrowing.

Not that this is a bad thing. Just interesting.

Cheers,
smudge

I have a Refrac, I keep it under my pillow, next to my false teeth.
However Plato is a philosopher and he won't fit under my pillow.

Andrew

 

[boybrewer]

I am no expert by far and I had a similar perplexing problem . What I found was that I took a gravity reading from the mash tun which left most of the sugars in it the reading was 1.042 and when I boiled it the reading was 1.042 go figure . I took the reading not from the boil kettle but the tun and that is where my answered lied .



cheers

 

[smudge]

Mmmmm, Andrew,

I know I'm a pedant but Plato WAS a philosopher. Still, if he's under your pillow.....do what you've got to do.

Cheers,
smudge

 

[NeilArge]

What I find interesting about this thread, is that some posters prior to the 14th post, assumed that Tunofgrunt was using a
refractometer...... talking Brix, undissolved solids etc.

Has our hobby come this far? Every man and his dog has a refrac? Mmmm....I do, and all of the brewers I know do too.

I reckon that soon we'll be quoting Plato instead of SG in the recipe database. The techology gap between professional
brewers and the great unwashed is narrowing.

Not that this is a bad thing. Just interesting.

Cheers,
smudge

I haven't done any research on this, so this is a dumb question probably. But is using a refractometer more reliable than using a hydrometer? I remember using one for testing the ripeness of grapes during my days in the Barossa, but that is a different story.

Cheers

On of the great unwashed! :icon_cheers:
ToG

 

[Kai]

What I find interesting about this thread, is that some posters prior to the 14th post, assumed that Tunofgrunt was using a
refractometer...... talking Brix, undissolved solids etc.

Has our hobby come this far? Every man and his dog has a refrac? Mmmm....I do, and all of the brewers I know do too.

I reckon that soon we'll be quoting Plato instead of SG in the recipe database. The techology gap between professional
brewers and the great unwashed is narrowing.

Not that this is a bad thing. Just interesting.

Cheers,
smudge

You know that degrees Plato can be and is measured by hydrometry, right smudge? Refractometers work in brix, not plato.

 

[manticle]

I haven't done any research on this, so this is a dumb question probably. But is using a refractometer more reliable than using a hydrometer? I remember using one for testing the ripeness of grapes during my days in the Barossa, but that is a different story.

Cheers

On of the great unwashed!
ToG

Refractometers in my very limited experience (watching someone else use one) are great because they only need a few drops rather than a tube vessel so less wastage. They are also easy to read. However once the beer starts fermenting, the reading is affected by the production of ethanol. I think there are ways around this (possible conversion???) but I'm not super sure. They're not an immediate, easy replacement anyway.

 

[AndrewQLD]

Mmmmm, Andrew,

I know I'm a pedant but Plato WAS a philosopher. Still, if he's under your pillow.....do what you've got to do.

Cheers,
smudge

Your right smudge, he WAS, although I wasn't having a shot mate, I thought it amusing how you said brewers were becoming more technical ( I read modern) and I chuckled over the Plato reference.
Oh well, my poor sense of humor is legendary, sorry :lol: .

Andrew

 

[Guest Lurker]

Yes but I think the main point from some of those posts is that break material shouldnt influence a hydrometer reading (does a boat float higher on a lake with fish in it, than it does on a lake with no fish? no it doesnt), whereas it could affect a refractometer reading.

 

[Kai]

Yes but I think the main point from some of those posts is that break material shouldnt influence a hydrometer reading (does a boat float higher on a lake with fish in it, than it does on a lake with no fish? no it doesnt), whereas it could affect a refractometer reading.

Could, if you have one of QLDKev's fancy brixomometers that just spits out a magic number. On a normal refractometer, suspended solids just make the line blurry (in my humble experience).

 

[Guest Lurker]

You should try dropping your refractometer so the line is askew instead of horizontal. Makes a brew day more interesting.

 

[smudge]

Andrew, I wish I was playing poker with you...I knew you were taking the piss but tried (unsuccessfully?) to take it up a notch.

Kai, I know refrac's use Brix, just taking it to where the curve looks like it's taking us. As far as Plato being a function of
hydrometry (or a result of its calculations), no, I wasn't aware. Thanks for the education. Really!

Cheers,
smudge

 

[sgc7of7]

Sorry to be a little less technical than everyone talking Brix and Plato, but I recently had a similar problem where my pre-boil and post boil gravity's were all upside down. While I'm not 100% sure of the cause, I suspect it is because of where I located the thermometer within my test tube (I used a test tube for both readings).

I found that letting the thermometer sit on the bottom of the test tube results in a much lower reading than if you hold the thermometer so that the bulb is suspended in the liquid. Obviously this screws with your conversions, so you may think you have a problem when you actually don't.

May not be your problem, TunofGrunt, but I thought I'd throw it out there....

Stephen

 

[NeilArge]

Sorry to be a little less technical than everyone talking Brix and Plato, but I recently had a similar problem where my pre-boil and post boil gravity's were all upside down. While I'm not 100% sure of the cause, I suspect it is because of where I located the thermometer within my test tube (I used a test tube for both readings).

I found that letting the thermometer sit on the bottom of the test tube results in a much lower reading than if you hold the thermometer so that the bulb is suspended in the liquid. Obviously this screws with your conversions, so you may think you have a problem when you actually don't.

May not be your problem, TunofGrunt, but I thought I'd throw it out there....

Stephen

Not quite sure what you mean, Stephen. Do you have the thermometer in the test tube as well as the hydrometer, and the thermometer blocks the free movement of the hydrometer? Sorry if I got that confused.

In the end, I think I'll follow Screwy's advice when I next brew and see what happens.

Cheers

ToG