The meaning for Champagne, which one is better? I found both in different reference books.
A white sparkling wine.
A sparkling white wine.
In English, as with many (most?) languages, there is a preferred order for adjectives, generally corresponding to various categories. However, the terms "sparkling wine" and "white wine" can be argued to be compound nouns, like "greenhouse" or "blackboard". They are both subcategories of wine. So, a red wine is still a red wine, even if you put food coloring into it and make it look purple, and a sparking wine is still a sparkling wine even if it has been left out and gotten completely flat. It is a whole unit that is inseparable, not an adjective modifying a noun.
This also means that adjective ordering generalizations do not correspond to the internal parts of these compounds. (This is why you have seen both orders used.)
So, if you are talking about white wines that are sparkling, you can call them "sparkling [white wines]". If you are talking about sparkling wines that are white, you can call them "white [sparkling wines]". Grammatically, they are equal in "correctness".
It's a sparkling white wine. A "white wine" is a major classification of wine, and "sparkling" is an extra adjective on top of that.