Ok. As promised (a long time ago) Some others have gone into more detail and built thier own kit, but I find this works well for my needs
The Kit comes with pretty easy directions to follow. As always, I suggest getting a separate sample of wine that you will throw away and NEVER TASTE this sample. you never know if you've gotten cross contamination somehow. (it's just good practice)
Put 15ml of wine into the testing cup.
Notice I wear rubber gloves. Just because I am a little anal anytime I deal with chemicals (even sanitizer).
For reds add 20ml of distilled water to lighten it and make the test easier to read. They say you can add up to 50 ML of water, but not more. I probably should have added a little more water to this test.
add 4 drops of the Phenolphthalein and mix. usually just mix by swirling the cup gently in your hand (no stiring needed).
Next, draw up 10 ml of Sodium Hydroxide into the syring. Add it one CC at a time and notice the color change. When it gets dark, and won't darken anymore you know that all the acid has been nutralized. So if you add 20ml you have .20 Acidity. 40ml = .40% acidity, and so on.
Here is the wine without any Sodium hydroxide added. NOTE: I didn't use it here, but I later found a LED light that was sold at Costco that I place under the cup. It lights the wine up and makes it much easier to read. The flash from my camera actually is easier to see than in real life. I suggest putting the cup on some sort of non-heat light source.
0ml of sodium
One 1 ML of soduim: (notice the darkening of the wine sample)
6ml As dark as it was going to get. Next ML didn't change so I didn't include the picture. I figured it was around .60%acid right about what I was hoping for.
Lastly, a couple of notes. if you get a kit like me, you only get one syring. you need to really wash the syring out between liquids. Meaning after adding wine, you need to wash the syring. Then after adding sodium you need to wash it.
White wines are MUCH simpler to use with this kit. I just so happened to be doing a red when my camera was handy. I used this same kit with my fruit wine and it worked great. No secondary light source was needed. The kit cost about $10. I have used it about six time and expect to get another 10-20 tests out of it. The kit also explains acid in pretty simple terms along with how to add and remove.
I'm sure there are more accurate tests if you are worried about ML fermentation, but for just knowing if you need to add an acid blend this kit is good 'nuff.
If I made a mistake please let me konw and I'll correct it.