White Wines and Lab Work part 1

Yesterday I started the lab work to see if the whites are ready to filter in preparation for bottling. The easy tests are for pH and titratable acidity. For the first I just calibrate the pH meter and then put the probe in the wine. TA’s are a little more work. I use both the pH meter probe and color to determine how much acid is in the wine. I do get to turn the wine a lovely pink color during the test and at least it looks like fun. Alcohols are also easy to check. I boil a small volume of wine and measure the temperature at which it boils. I look at chart and read off how much alcohol is in the wine.

Checking free SO2, which is the amount of sulfide available in the wine to protect it, is another quick and easy test, though again I have to trust my eyes. I am simply looking for color change. To the left you can see a finished sample, one in the midst of testing and the last about to be tested.

Checking residual sugar is probably the slowest test. It certainly has the most steps but does get to go through the most color changes which keeps me entertained. I won’t tell you all the details other than there are 6 chemicals, early on the solution gets boiled for one and half minutes and in the end I have to trust my eyes.