Choosing a tea base: Black tea kombucha’s strong flavor pairs well with the sweetness of the grapes. White tea or green tea kombucha complements the earthiness of the grapes and creates a more mellow flavor. Oolong tea kombucha makes a light, fragrant kombucha juice.

White grape juice is lighter and crisper than purple grape juice. Use the flavor you prefer. Look for store-bought juice that has no added sweetener or ingredients.

Alternatively, juice your own grapes. Choose any store variety—darker grapes have a more robust flavor. As you juice them, remove the grapes by cutting the stem. If you pull individual grapes and leave behind a long stem, the remaining grapes will dry out more quickly.