Yet another thing I learned on my last brew day

[redrocker652002]

So, I was brewing a Pale Ale, moving along nicely. Took a gravity check pre boil and it was at something like 1.049. Not too bad since Brewfather said I should be at about 1.048. Feeling pretty good about myself. So, off I go to the boil. Moving along, I am in the last few minutes of the boil, so I take a plato measurement. Ummm, it equated to about 1.065, holy crap. Brewfather said I should have been somewhere in the 1.055 area. As did the recipe I used as a starting point. So, here I am thinking I got way over where I should be. Well, I let the wort cool off in a small glass and tested it again. Damn if it wasn't at about 1.058. So, I am now a bit confused, so I do a hydrometer test. Same thing, 1.058 or so. So, moral to the story, make sure your wort is cool before you check it, or else you will think you are way higher than it should be. LOL. Now, it is sitting in the new fermenting chamber at about 64 degrees. Took about 12 hours for the Bry 97 to kick in, but it was moving along nicely when I left the house this morning. Will check it when I get home. Anyway, chalk it off to another learning experience. Rock On!!!!!!!

 

[doug293cz]

If you take a very small, hot sample for a refractometer, you need to do it in a way that does not allow for evaporation from the sample. Best to use an eyedropper or a syringe to take the sample. With a small sample, evaporation can easily give you an erroneously high SG reading.

Brew on

 

[lumpher]

https://www.brewersfriend.com/hydrometer-temp/

 

[doug293cz]

https://www.brewersfriend.com/hydrometer-temp/

Warm hydrometer samples read too low, not too high.

Brew on

 

[redrocker652002]

Warm hydrometer samples read too low, not too high.

Brew on

Well, all I can say is my reading went from 1.064 or so to 1.058 once things cooled off a bit. LOL. But, with that said, a buddy came over and we started drinking and shooting the bull. But I am sure that the readings were higher when it was hotter.

 

[doug293cz]

How did you measure the sample that was 1.064 - 1.065?

Brew on

 

[redrocker652002]

How did you measure the sample that was 1.064 - 1.065?

Brew on

Using a refractometer. It is new to me, so I may have read it wrong. But I did it a few times and kept getting the same thing. Once the sample cooled as well as a larger sample in my hydrometer, they both read in the area of 1.058. So, maybe I did something wrong. Who knows. I just thought it was kinda funny

 

[redrocker652002]

Thank you to the mod for moving this to the proper forum. I appreciate it, and was not sure where it should have been Rock On!!!!!!!!

 

[Jag75]

Before you took a reading at the cooler temp did you by chance rinse the dropper out with water ? If so and it wasn't thoroughly dry your next sample could have been diluted.

Edit* However that doesn't explain the hydrometer reading . Nvm

 

[redrocker652002]

Before you took a reading at the cooler temp did you by chance rinse the dropper out with water ? If so and it wasn't thoroughly dry your next sample could have been diluted.

Edit* However that doesn't explain the hydrometer reading . Nvm

Great question as I would not have thought of that, so I am glad you posted. No, I did not because I used a Qtip and swirled it around the wort after I did the boil. It came from the top of the pot, so maybe I was a bit off by posting this to begin with. Maybe the bottom of the pot would have given me a different reading? It was while the wort was still boiling so I think I am ok. But, with that said, maybe that has something to do with it? Either way, it is happily fermenting in my new fridge fermenter box set at 65. Hopefully in about a week I will put the dry hops in, maybe drop the temp down for a mini cold crash to get some of the stuff to settle and into the keg it will go.

 

[doug293cz]

Great question as I would not have thought of that, so I am glad you posted. No, I did not because I used a Qtip and swirled it around the wort after I did the boil. It came from the top of the pot, so maybe I was a bit off by posting this to begin with. Maybe the bottom of the pot would have given me a different reading? It was while the wort was still boiling so I think I am ok. But, with that said, maybe that has something to do with it? Either way, it is happily fermenting in my new fridge fermenter box set at 65. Hopefully in about a week I will put the dry hops in, maybe drop the temp down for a mini cold crash to get some of the stuff to settle and into the keg it will go.

At the end of the boil, the wort is well homogenized, and it will not spontaneously stratify after the boil stops. Stratification can be an issue prior to boil if you sparge, or if you do partial boils and dilute after the boil.

Tell us more about this QTip sampling technique, and the instrument into which you place that sample. My first impression of a QTip sample collection is that it is the worst possible method for evaporation from a sample, which will make it read high.

Brew on

 

[redrocker652002]

At the end of the boil, the wort is well homogenized, and it will not spontaneously stratify after the boil stops. Stratification can be an issue prior to boil if you sparge, or if you do partial boils and dilute after the boil.

Tell us more about this QTip sampling technique, and the instrument into which you place that sample. My first impression of a QTip sample collection is that it is the worst possible method for evaporation from a sample, which will make it read high.

Brew on

Not much to really say. I dipped the tip in the wort, swirled it around a bit then I squeezed the end of the qtip onto the glass of the refractometer. The warmer wort read higher. I put some into a glass cup and put it on the counter to cool. Did the same thing using the same method and it read much closer to the recipe's OG predictions. I then took a bigger sample and put it in my hydrometer tube and put that in the fridge to cool. Took a reading with the hydrometer and it was just about the same as my cooled refractometer reading. Again, please note, that my buddy came over and we had a few beers while I was doing all this. LOL

 

[doug293cz]

Ok, I'm certain that your high reading of the right after boil wort was due to water evaporation from the hot QTip sample. If you use an eyedropper or syringe, you will just about eliminate any false reading due to evaporation.

Brew on

 

[redrocker652002]

Ok, I'm certain that your high reading of the right after boil wort was due to water evaporation from the hot QTip sample. If you use an eyedropper or syringe, you will just about eliminate any false reading due to evaporation.

Brew on

OK, I will try that next time, but why would my readings change using the same process on a cool wort off the same style Qtip? Also, it literally took me maybe 2 seconds to get the Qtip from the kettle to the refractometer. It could change that quickly? I am not saying you are wrong, just a bit unsure how that could be. Either way, I will try it with an eyedropper next time if I have one. Thanks for the info and taking the time to post. Rock On!!!!!!

 

[jdauria]

Using a refractometer. It is new to me, so I may have read it wrong. But I did it a few times and kept getting the same thing. Once the sample cooled as well as a larger sample in my hydrometer, they both read in the area of 1.058. So, maybe I did something wrong. Who knows. I just thought it was kinda funny

Did you calibrate the refractometer? Usually you need to take a hydrometer reading and a refractometer reading, plug in in to the refractometer calibration tool in BrewFather. It then gives you a "correction factor". Than when you take a refractometer reading (in Brix), you enter that in Brewfather and it will apply the correction factor and give you the proper reading in gravity points. Also you are better using this method and taking the Brix reading from refractometer than the gravity reading, as refractometer gravity readings tend to not always be accurate. Lastly, did you put distilled water on refractometer and make sure it read zero? If it doesn't, you need to adjust the little screw (usually under a cover) on it to make sure it reads zero.

 

[doug293cz]

OK, I will try that next time, but why would my readings change using the same process on a cool wort off the same style Qtip? Also, it literally took me maybe 2 seconds to get the Qtip from the kettle to the refractometer. It could change that quickly? I am not saying you are wrong, just a bit unsure how that could be. Either way, I will try it with an eyedropper next time if I have one. Thanks for the info and taking the time to post. Rock On!!!!!!

Hot wort will lose water due to evaporation if it is not contained. The larger the surface area to volume ratio, the faster the evaporation occurs (at any given temperature.) A sample taken with a QTip will have a very high surface area to volume ratio.

Brew on

 

[redrocker652002]

Hot wort will lose water due to evaporation if it is not contained. The larger the surface area to volume ratio, the faster the evaporation occurs (at any given temperature.) A sample taken with a QTip will have a very high surface area to volume ratio.

Brew on

Very cool. I did not even think about that. Many thanks for the info. Going to get a small dropper and see if that changes things.

 

[redrocker652002]

Did you calibrate the refractometer? Usually you need to take a hydrometer reading and a refractometer reading, plug in in to the refractometer calibration tool in BrewFather. It then gives you a "correction factor". Than when you take a refractometer reading (in Brix), you enter that in Brewfather and it will apply the correction factor and give you the proper reading in gravity points. Also you are better using this method and taking the Brix reading from refractometer than the gravity reading, as refractometer gravity readings tend to not always be accurate. Lastly, did you put distilled water on refractometer and make sure it read zero? If it doesn't, you need to adjust the little screw (usually under a cover) on it to make sure it reads zero.

No I did not. I will though, but it read pretty much spot on with my hydrometer. The refractometer is new to me and I am still trying to figure out how it works and what I need to do. I will check it out. Also, this particular meter only does Brix, so I use Brewfather to convert it to Gravity, it that makes sense.

 

[Hoochin'Fool]

If you take a very small, hot sample for a refractometer, you need to do it in a way that does not allow for evaporation from the sample. Best to use an eyedropper or a syringe to take the sample. With a small sample, evaporation can easily give you an erroneously high SG reading.

Well that would certainly explain some erratic refractometer readings I've seen, from readings taken mid-boil!

 

[redrocker652002]

And the hits just keep coming. Another first for me. I guess the airlock got blocked up by the krausen. I came home yesterday after work and checked on the fermenting only to find a nice small puddle of stuff near the door of the fridge I am using. I open the door to find a small puddle around the bucket as well and the airlock full of krausen. So, I took the airlock out, and when I did, the pressure sprayed stuff all over me. Cool, I chose to look at it as I am having a great ferementation on this one. So, I clean up the airlock, put it back and off I go. Now the yeast was added to the wort on the 8th, so we are only a few days in, but I figure it should be calming down soon. Well, I get home from work this morning and what do I find? Another small puddle and another blowout. LOL. So, I clean it up, clean up the airlock and put everything back again. First time that has happened. Might think about using a blowoff tube next time.