Q: How long after adding acid blend and mixing should I wait before re-testing my pH? I’ve not been able to find this information in past articles.
— Jack Kerr — Santa Fe, New Mexico

A: The answer to your question depends on the size of your batch. The bigger your batch, especially if it’s must all mixed together with juice and skins, you need to mix quite a bit longer. Let’s say for example you have a 5-gallon (19-L) carboy of Chardonnay juice and you are adding 1 g/L tartaric acid dissolved in a little water, then you could probably stir the solution into your carboy with a stirring rod for about a minute, let it sit for about 30 minutes and then re-sample.

For a big 60-gallon (227-L) trash can full of must, it’s probably a good idea to do a good 5-minute punch down, wait 30 minutes and do another one before re-sampling for a pH or TA test. It is very important that you mix your containers well before re-sampling. The chemical effect of dissolved acid blend on pH is immediate (with complete stirring). I hope this gives you some good guidance.