TA is the easiest, you just need 0.1N (or similar) NaOH. Titratable acidity (at least in the US) involves titrating your sample to pH 8.2 endpoint, which is why you can use phenolphthalein - that's where it changes from clear to pink. I prefer to use the pH meter since the phenolphthalein color fades with time, so you need to titrate 'fast' - too slow and you run the risk of over-titrating. It's not hard, but there is a bit of a technique to it.
SO2 by Ripper method is very fast, you add sulfuric acid and starch indicator to your sample and titrate until you get a dark purple color. Like the TA/phenolphthalein titration, the color fades eventually so you have titrate fairly rapidly. Disadvantages to Ripper method are (a) it's harder to see the endpoint in red wine, so you have to dilute out your samples and (b) Iodine solution isn't stable so you need to calibrate it from time to time. There is an alternative protocol using potassium iodide/potassium periodate which overcomes the stability issue. I think the Vinmetrica uses this method but with a potentiometric probe instead of color indicator.
SO2 by Aeration/oxidation method... you need some sort of apparatus to bubble air through your sample, through a tube and into an indicator vessel. Basically the SO2 liberated from the sample is converted to sulfuric acid in the indicator vessel (turns the indicator pink), then you titrate it with 0.01N NaOH until the pink color goes away. It's not affected by wine color and is considered the gold standard in wineries, but it is much slower, 10 minutes for bubbling the sample plus set up and titration time. Here is my AO setup. The sample is in the round bottomed flask on the left in the ice bath. SO2 is liberated from the (acidified) sample and is drawn into the indicator vial (pink); vacuum pump is on the right.
View attachment 108736
YAN - as I said I haven't done this but it seems doable with appropriate reagents. I would ideally do this in a fume cabinet, but since most of us don't have one lying around the house I would at least open all the windows when using formaldehyde. I believe
@Rice_Guy mentioned home-lab YAN assays in a recent thread, so he may be better placed to comment.
References:
Free SO2 by Ripper:
https://www.enartis.com/wp-content/uploads/2020/04/SO2-Free-by-Ripper.pdf
Free SO2 by Ripper (includes method for standardizing Iodine):
http://seniorchem.com/8. Sulfur-Dioxide-by-Ripper-Titration.pdf
Alternative Ripper method:
https://biomedress.com/pdf/CJBRT-19-22-034.pdf
Free SO2 by AO:
https://www.enartis.com/wp-content/uploads/2020/04/S02-Free-by-AO.pdf
Edit: typos