Review on 🍺 Crafting Excellence: Explore Midwest Homebrewing and Winemaking Supplies by Dusty Oner

They work. But for me it was very approximate. Depending on the degree of acidity, I did get a color change, but it wasn't as dramatic as expected because the paper already had a yellow tinge. Add to this the difficulty of discerning colors when immersed in colored liquids and you have something vaguely informative. and difficult to use. It's cheap, but next time I need to check acidity I'll buy a titration kit.