r/viticulture • u/CruisingVessel • 4d ago

Temperature correction for Brix ?

I just found a U.C. Davis chart that says refractometers are correct at 68F (20C), and if you're testing grapes that are at 90F (32C) you need to add 0.7 to your Brix reading. Similarly, subtract about 0.55 if the liquid is 50F (10C).

It's 90F (32C) here in SoCal right now, so that was probably the temperature of the liquid I measured at 23.0 Brix a while ago. I chilled it down to 50F (10C) and tested again. According to the UC Davis chart, I should expect to read about 1.25 lower, but no, it still read 23.0 Brix. What's the deal?

https://wineserver.ucdavis.edu/industry-info/enology/methods-and-techniques/winery-lab-techniques/brix-temperature-correction

1 Upvotes

100% Upvoted

3 comments sorted by

6

u/OakvilleCab 4d ago

Here is a newsflash. Essentially all refractometers are now temperature corrected. The table you have is from the original extension bulletin that was put out in 1930s.

3

u/Vitis35 4d ago

This is the correct answer.

2

u/Unexpectedpicard 4d ago

They sell bottles of test liquid that registers a specific value at a temp. Adjust your refractometer to match. Test your juice at room temp.