The good news for tourists is that, as in the past warning, most popular areas (including Cancun, the Riviera Maya, Mexico City, Los Cabos, Riviera Nayarit, Puerto Vallerta, San Miguel de Allende, Guanajuato, Merida, Chichen Itza, Huatulco and Oaxaca) are exempted.
Super Chill Mountain Chill Soda Ingredients Carbonated Water, High Fructose Corn Syrup, Orange Juice From Concentrate With Other Natural Flavors, Citric Acid, Potassium Benzoate (A Preservative), Gum Acacia, Potassium Citrate, Caffeine, Calcium Disodium Edta (To Protect Flavor), Yellow 5, Brominated Vegetable Oil
For one teaspoon baking powder = mix 1/2 teaspoon cream of tartar plus 1/4 teaspoon baking soda. If you are not using immediately, add 1/4 teaspoon cornstarch to absorb any moisture in the air and to prevent a premature chemical reaction between the acid and alkali.