Cream of Tartar is a food ingredient commonly added to cookies, eggs, candy and other baked goods. It’s also been commonly recommended in Facebook groups in something called an Adrenal Cocktail to supplement potassium. It’s also great at cleaning brass and other metals.
Cream of Tartar is made with tartaric acid and potassium hydroxide. Most tartaric acid comes from wine making, which is where sulfites are introduced. Potassium hydroxide is Lye or caustic potash, which is common, so the source could be from anywhere.
To keep microbial activity down in wine making, as well as anti-oxidize the wine, sulfur dioxide is used. This ends up creating sulfites in the wine, which end up in the tartaric acid used to create Cream of Tartar.
Sufiltes are so common in wine making that some people claim wine without sulfites would be completely different chemistry This means any Cream of Tartar created from wine will have some level of sulfites.
The best alternative to Cream of Tartar is fresh lemon juice. Use twice as much lemon juice. Vinegar, buttermilk or yogurt can substitute as well. Organic baking powder also works.