Tilt Hydrometer reading wrong SG wort

[RudeBooch]

So im brewing hard kombucha. After calibrating the tilt meter to the app, i get a refractor meter reading and dunk the hydrometer in the tank. After a couple of days, my SG wort went from 1.051 to 1.015. Of course i double checked it and clearly was off. I had recently changed from using water in my airlock to vodka. Do you think that can be the factor? I’ve never really had this issue until now.

 

[Spivey24]

I don’t think I follow. Your saying your final gravity was 1.015 on the Tilt but your hydrometer read differently? What was the Tilt reading uncalibrated? Does hard kombucha have a scoby to duck with it? What does vodka in the airlock have to do with your FG reading.

 

[RudeBooch]

Yea i dont think i worded that correctly. My starting gravity was 1.051 with the refractometer. Thats what i set it as on the tilt app as the actual sg to start. When i went to check the notes from the tilt a day and a half later, it read 1.015, but when i double checked with the refractometer, it was a 1.045. im not sure how the tilt hydrometer made that jump in suchba short time.

 

[schmurf]

Tilt might show wrong values sometimes when it's stuck in a thick krausen.

 

[RM-MN]

Yea i dont think i worded that correctly. My starting gravity was 1.051 with the refractometer. Thats what i set it as on the tilt app as the actual sg to start. When i went to check the notes from the tilt a day and a half later, it read 1.015, but when i double checked with the refractometer, it was a 1.045. im not sure how the tilt hydrometer made that jump in suchba short time.

Refractometers do not read directly when alcohol is present but need a correction factor. The kombucha could have fermented pretty quickly so the 1.015 reading might be correct. You would need to use a hydrometer, not a refractometer to verify the Tilt reading.

 

[brewbama]

I recommend calibrating the Tilt in water to 1.000. I have tried the “known SG” method and wasn’t satisfied. I am unfamiliar with kombucha fermentation. If anything interferes with the Tilt (i.e. krauzen) it will be inaccurate.

 

[Jag75]

Was your tilt and refractometer reading the same results prior to fermentation?

 

[Spivey24]

Although a refractometer needs a correction factor when alcohol is present, it’s not that much at 1.045 from 1.051.

Also, I wouldn’t calibrate the Tilt against a refractometer for known gravity, but unless it was far from factory, then not you issue. How far was the calibration from factory?

The tilt might be stuck on something. Give the fermenter a bit of a shake. It it doesn’t help, you will just have to wait until you retrieve it to check again.

 

[rburrelli]

Yea i dont think i worded that correctly. My starting gravity was 1.051 with the refractometer. Thats what i set it as on the tilt app as the actual sg to start. When i went to check the notes from the tilt a day and a half later, it read 1.015, but when i double checked with the refractometer, it was a 1.045. im not sure how the tilt hydrometer made that jump in suchba short time.

Double check with a hydrometer.

 

[myndflyte]

I've found the Tilt is always a bit off from my final hydrometer reading. I rely on the Tilt to give me a representation of what fermentation is doing, not so much what the actually gravity is. That being said, the numbers aren't usually that far off, but like others have said, measuring fermented liquids with a refractometer needs a correction factor. I would recommend getting a hydrometer for fermented measurements.

 

[Yooper]

Refractometers read the refraction of light in a sugar solution. I use my Tilt, but only in beer (the instructions say not to use it in wine, and I would assume kombucha is the same way).

With kombucha, there are multiple fermentations taking place since first some of the sugar is converted to alcohol, while lactobacillus is simultaneously happening, and then acetobacter converts the alcohol to vinegar and water. So a hydrometer is pretty useless in kombucha, as would be a tilt.

 

[RudeBooch]

Was your tilt and refractometer reading the same results prior to fermentation?

Yea it was pretty close. Theres about a 1.003 difference on most of my batches give or take.

 

[RudeBooch]

Although a refractometer needs a correction factor when alcohol is present, it’s not that much at 1.045 from 1.051.

Also, I wouldn’t calibrate the Tilt against a refractometer for known gravity, but unless it was far from factory, then not you issue. How far was the calibration from factory?

The tilt might be stuck on something. Give the fermenter a bit of a shake. It it doesn’t help, you will just have to wait until you retrieve it to check again.

I reached out to tilt about it. The issue was actually when i calibrated the tilt with water. It gave me a reading of 0.000-1.000 automatically and thats what threw off my numbers. After deleted that note from the settings and getting real readings from a hydrometer, the gravity seems stable now. I was getting numbers going below 1.000 after 2 days in the ferment.

 

[jtgoral]

I think Tilt depends on the device's tilt angle to measure the gravity. Any fermentation crap collecting on the top of the Tilt's tube will make it tilt more and show higher gravity.
If the tube's bottom hits the wall of the fermenter it can tilt less and show smaller gravity.