when do i need to check pH?

[pilotdentist]

First two batches I did were from wine concentrates I bought online. From the reading I have done, I understand you do NOT have to check pH, as they already balance it for you.

For my 3rd brew, I bought a "California White" concentrate from a local winery. Any idea if ones like this (picture below) already have a balanced pH? Or do you only need to check pH if you start with raw grapes? I already started fermenting, but could check pH before bottling, if needed. Also, it did not have any directions besides "add 2 pounds of granulated sugar". I plan on basically using the recipe for a Chardonnay I bought (adding yeast nutrient halfway through primary fermentation, adding oak chips to secondary fermentation, adding potassium sorbate, potassium metabisulfite, chitosan, kietesol etc for clearing and before bottling).

Let me know if you have any other general advice on pH testing. Thanks!

 

[Rice_Guy]

Once you are fermenting the yeast are producing CO2 which decreases the pH sooo a reading now would not be stable. I have the meter and it is a zero cost test so I check at the start.

Grapes are close to where one wants to be so you could let it go. Country wines ALLWAYS have to get pH checks and acid adjustment since they can be way low (cranberry) or high (peach/ banana/ zucchini).
When you bottle you make adjustments for flavor. This assumes that the pH was where you wanted it when you started.

Not stated but with a pH meter it is easy to run TA. This technically is the determinant of how much bite the pH (acid) does in your mouth.

 

[pilotdentist]

Thanks rice_guy. So grapes concentrates are usually the 3-4 desired pH and fruit wines are all over the place.

Follow on question:
Should I have added campfent tablets before fermentation to kill wild yeast, or is that not a concern for concentrates like the one pictured?

Also, does the SO2 released from a camp den tablet only work for a day, so adding my own yeast 24 hours after use is alright?

thanks!

 

[pilotdentist]

Just read on the label it says “grape juice concentrate potassium metabisulfite”

so I would think it’s already in there and no campden would be necessary before fermentation.

 

[Scooter68]

With any prepared juice concentrate you need to read the label and if that doesn't tell you test it yourself or call/write the maker find out from them. Most good sellers can tell you if the product is already balanced or if it's just raw juice. Suppliers generally like to provide consistent products especially if they are dealing with large purchasers of their products or even if they are selling to home wine makers. If they frustrate either one their business suffers BUT it pays to check with them and also check it yourself - especially if the product is getting close to the "Use by" date.