Using a refractometer, I am confused.

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sodbuster

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Hey can you guys help me understand something. I use a refractometer and online calculator but I don't think I am doing something right.

The last beer I made using the refractometer had a OG of 1.065 or 16B. It is now at 1.027 or 6.7B.
Using the online calculator my abv is currently 8.24 or 8% depending on the site.
My adjusted current SG is 1.003

That seems really high to me, I punched my ingredients into a recipe calculator and it said the (i am working on efficiency) OG should be 1.069 and final 1.017 with a abv of 6.77.

I don't have a hydrometer to double check my work. Am I using the calculator wrong or did I just have a amazing fermentation?

Thanks
 

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Without a hydrometer at all, we won’t know your wort correction factor (remember that refractometers read sucrose in a liquid, and not some of the other things in beer wort), but you can guess by using the calculator.
It’d be hard to believe that your FG is 1.003, though.
 

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You are using the calculator correctly.

Maybe the recipe prediction was wrong? Recipe, yeast type?

Maybe the reading was misread? 8.7Bx maybe? Check it again?
 
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sodbuster

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@DBhomebrew

25lbs of 2row
5lbs carmel 10
1.5 lbs rolled oats
And 2 packets of safale 05 but I also dumped all that on top of a yeast bed of English ale yeast that was leftover from the previous brew in the fermentor.

But the previous brew has similar stats. Started with 17b and now at 8b
 

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Are you inputting a wort correction value into the calculator?
Since you don't have a hydrometer to calibrate your wort correcting factor, you can use a factor of 1.04 for a typical wort correction.
Using a wort correction value of 1.04, an original brix of 16B, and current brix of 6.7B - I get an ABV of 7.2%
 

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The WCF is a rather small adjustment.

The discrepancy is a large deviation from a recipe targeting a FG around 1.017, attenuation around 75%.

OP's reported Brix values in the Brewer's Friend calculator give an attenuation of 93.8% (WCF 1.0) or 93.6% (WCF 1.04).

The question isn't of 93.8 vs 93.6, it's ~93.5 vs ~75%.

I suspect an error in measuring or notation.
 

dmtaylor

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The WCF is a rather small adjustment.

The discrepancy is a large deviation from a recipe targeting a FG around 1.017, attenuation around 75%.

OP's reported Brix values in the Brewer's Friend calculator give an attenuation of 93.8% (WCF 1.0) or 93.6% (WCF 1.04).

The question isn't of 93.8 vs 93.6, it's ~93.5 vs ~75%.

I suspect an error in measuring or notation.

+1 Possible contamination as well, but I'm hoping it's just a measurement error.
 
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sodbuster

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The WCF is a rather small adjustment.

The discrepancy is a large deviation from a recipe targeting a FG around 1.017, attenuation around 75%.

OP's reported Brix values in the Brewer's Friend calculator give an attenuation of 93.8% (WCF 1.0) or 93.6% (WCF 1.04).

The question isn't of 93.8 vs 93.6, it's ~93.5 vs ~75%.

I suspect an error in measuring or notation.
The first beer I measured about 4 times as I was trying to get the OG up, I have a new brewery and blew the mash process so I ended up adding honey to get to the 17B. The aforementioned pale ale I don't recall measuring the SG more than once but I know I wrote it down correctly because I thought it was high when I read it.
I think I pulled the sample from the bottom of the brew kettle after transferring the wort to the chronical. Maybe I sucked up a floaty or something, or the sugars were resting in the bottom of the pot?
 

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The first beer I measured about 4 times as I was trying to get the OG up, I have a new brewery and blew the mash process so I ended up adding honey to get to the 17B. The aforementioned pale ale I don't recall measuring the SG more than once but I know I wrote it down correctly because I thought it was high when I read it.
I think I pulled the sample from the bottom of the brew kettle after transferring the wort to the chronical. Maybe I sucked up a floaty or something, or the sugars were resting in the bottom of the pot?

Well, for a good reading you must be sure to fully homogenize the wort before taking a sample. This is most important pre-fermentation. Sugar heavy water likes to stratify.

That said, it's the FGs that are so far out. Could you take another reading on the most recent? Confirm the 6.7Bx?
 
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sodbuster

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Thank you for your help guys, this place is awesome. Outstanding that the braintrust will take time to help someone and nobody told me to use the search function.

Going forward I will chase down a refractometer, I used to have one but broke it years ago. I know the final abv is not important but I am trying to dial in my new brewery and I wanted to make sure I am getting accurate readings throughout the process.
 
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sodbuster

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Well, for a good reading you must be sure to fully homogenize the wort before taking a sample. This is most important pre-fermentation. Sugar heavy water likes to stratify.

That said, it's the FGs that are so far out. Could you take another reading on the most recent? Confirm the 6.7Bx?
Yep, Stand by
 

DBhomebrew

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nobody told me to use the search function

It's in the rule book and just plain unfriendly!

14. No use of "Google it", or "Try Searching". If a question has been answered before, answer it again or with nicely provide a link rather than copying/pasting content from elsewhere on the forum. Berating or poking fun at "noobs" for not searching will not be allowed.

 
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sodbuster

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7.1B
Using the same method as before, dumping from the racking arm into a mason jar and sampling from there, the difference being that on the first try I was clearing a lot of yeast through that port.
 
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I need to get a hydrometer to double check my work and get my wort correction factor, Ill ask how to do that when I pick one up.
 

DBhomebrew

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Is your refractometer ATC? Auto temp control? Do you store it at roughly the same temp of your samples?

How fresh was the English ale yeast cake? Kept nice and sealed?
 
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Is your refractometer ATC? Auto temp control? Do you store it at roughly the same temp of your samples?

How fresh was the English ale yeast cake? Kept nice and sealed?
Yep it is ATC and its in the basement beside the fermentor. The english ale yeast was brand new on the prior brew, I used it to make a Blackberry Milkshake IPA. I dumped it into carboys using the racking arm then I dumped the pale ale into the fermentor and added the safale 05.
I play it fast and loose can you tell?
 

DBhomebrew

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Yes, indeed.

Before bothering with WCF, I highly recommend dialling in your sample collection methods until you get highly repeatable results.

6.7 vs 7.1 isn't all that far off. Well within the range of a beginner using the tool for the first few times.

So, this batch is somewhere around 1.003-007. Either way, that attenuation is super high for those yeast in a normally mashed wort of that grist.

Work on your refractometer skills. Do a thorough cleaning and sanitizing of any and all of your gear before the next batch. Seriously. Every nook and cranny.
 

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The first beer I measured about 4 times as I was trying to get the OG up, I have a new brewery and blew the mash process so I ended up adding honey to get to the 17B. The aforementioned pale ale I don't recall measuring the SG more than once but I know I wrote it down correctly because I thought it was high when I read it.
I think I pulled the sample from the bottom of the brew kettle after transferring the wort to the chronical. Maybe I sucked up a floaty or something, or the sugars were resting in the bottom of the pot?

Honey is much more dense than wort and will sink to the bottom quickly. It takes a lot of stirring to get it to properly dissolve. That might have given you a false OG reading.

Take a glass tumbler, fill it 3/4 with water. Put in half a teaspoon of honey and watch where it goes. Now try to stir it until it completely dissolves....using only a toothpick. That's what it is like stirring honey into a 5 gallon batch with a spoon.
 

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Honey is much more dense than wort and will sink to the bottom quickly. It takes a lot of stirring to get it to properly dissolve. That might have given you a false OG reading.

100%. And if true, it would only increase the crazy high attenuation.

Wait. Tell us about this...

How did you blow the mash?
How much honey did you add? What was the gravity before the honey?
 

dmtaylor

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7.1 final Brix instead of 6.7 Brix is quite a difference. Your FG and attenuation then are more reasonable at about 1.007 and 89%. Still high, but adding honey will cause this since honey has simple sugars and is nearly 100% fermentable. All makes sense to me now, if that's what's happened. Otherwise 89% attenuation is still kind of high, but not completely unheard of.

I should add that you need to check the refractometer in plain room temperature water to ensure it reads 1.000. Mine doesn't. It might be a little off, so you might need to add or subtract like 0.2 Brix if a little off. Assuming yours would read 1.000 in plain water...

Here's what you've got based on the most reliable calculator at Brewer's Friend:

1659883069464.png
 
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sodbuster

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Yes, indeed.

Before bothering with WCF, I highly recommend dialling in your sample collection methods until you get highly repeatable results.

6.7 vs 7.1 isn't all that far off. Well within the range of a beginner using the tool for the first few times.

So, this batch is somewhere around 1.003-007. Either way, that attenuation is super high for those yeast in a normally mashed wort of that grist.

Work on your refractometer skills. Do a thorough cleaning and sanitizing of any and all of your gear before the next batch. Seriously. Every nook and cranny.


Thanks! I guess I should have mentioned that I have been brewing for roughly 15 years, always all grain. I have been using the refractometer almost as long. Hence the original question, I was really thrown off by the attenuation. I have been brewing 10 gallon batches in the garage using gravity and a cooler for the last 9 years or so and recently built a brewery in the unfinish basement of our new house (work in progress). I rarely follow recipes but on occasion I do like the Blackberry milkshake ipa. I have had 2-3 batches spoil in all those years and every time I was able to trace it back and realize where I had contaminated.
Cleaning the fermentor is a pita so I tend to use it twice before breaking down and sanitizing, I finally ordered some butterfly valves so I don't have to breakdown the ball valves which is a pita.
I enjoy brewing but I try not to over complicate the process.
I will standardize my sampling method going forward to get repeatable results.
 
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sodbuster

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Honey is much more dense than wort and will sink to the bottom quickly. It takes a lot of stirring to get it to properly dissolve. That might have given you a false OG reading.

Take a glass tumbler, fill it 3/4 with water. Put in half a teaspoon of honey and watch where it goes. Now try to stir it until it completely dissolves....using only a toothpick. That's what it is like stirring honey into a 5 gallon batch with a spoon.
The honey was added to the BB Milkshake IPA. I am a beekeeper with about 40 hives so I always have plenty laying around and often a mead on tap.
 
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sodbuster

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100%. And if true, it would only increase the crazy high attenuation.

Wait. Tell us about this...

How did you blow the mash?
How much honey did you add? What was the gravity before the honey?
Blew the mash on the BB Milkshake IPA, it was the first brew with my new set up. Basically I do (and my terminology is not on the level of you guys) batch mashing in SS brewtech infusion, I have the capability to HERMS but I haven't the coil and plenty of time for that later.
So my strike water was pitched into the mash tun at roughly 165 degrees a number sometimes used with my old set up. After a few minutes the probe reading to the controller was 135 degrees so I panicked and heated up some 190 degree water and threw it on top (I know dumpster fire). Still 135, finally I did what I should have done to start with and grabbed my javelin pro to double check the mash temp and it was 170 something, so I added cold water, now it was 145 lol... So I pumped all that hot mess back into the HLT and heated it to 156 and put it back into the mash tun where it settled at 151 for a hour. Now I have no idea how much mash water I had, it did run clear with Iodine test though.

The probe was 2.5" and barely reaching into the insulated mash tun so I ordered a 5" probe and no longer have that problem.

I don't exactly recall the gravity before I added the honey, I was shooting for 1.067 and I think it was like 1.050, I have a 5 gallon bucket of honey I was just dumping it in the pot and rechecking until it hit 1.067, then the final step of the brew I added 2 lbs of lactose which I didn't realize is sugar, lol and that got me to 1.070.
 
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sodbuster

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7.1 final Brix instead of 6.7 Brix is quite a difference. Your FG and attenuation then are more reasonable at about 1.007 and 89%. Still high, but adding honey will cause this since honey has simple sugars and is nearly 100% fermentable. All makes sense to me now, if that's what's happened. Otherwise 89% attenuation is still kind of high, but not completely unheard of.

I should add that you need to check the refractometer in plain room temperature water to ensure it reads 1.000. Mine doesn't. It might be a little off, so you might need to add or subtract like 0.2 Brix if a little off. Assuming yours would read 1.000 in plain water...

Here's what you've got based on the most reliable calculator at Brewer's Friend:

View attachment 777071

I took a bottle of water out of the fridge this morning so its cold but reading about .5B below 0. I will let it warm up to room temp which is 65 and re check, re calibrate the refractometer for the next brew.
 
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