In your first sentence, the comma indicates an apposition. In your sentence you have first the description of the referent, followed by the referent itself. Maybe more usual would be the reverse order: (Cambridge)
The second noun phrase tells us something more about the first noun phrase (its identity or its qualities).
- [NP 1] Timothy, [NP 2] their youngest child, is very musical.
We can also reverse the order of the phrases:
- [NP 1] Their youngest child, [NP 2] Timothy, is very musical.
So yes, in your sentence the NP 1 (one of the “Most Beautiful Villages in France”) is the apposition having as a referent NP 2 (Riquewihr).
As for such as, it is used to introduce a non exhaustive list of examples: (Cambridge)
We can use such as to introduce an example or examples of something we
mention. We normally use a comma before "such as" when we present a list
of examples. Where there is just one example, we don’t need a comma:
- The shop specialises in tropical fruits , such as pineapples, mangoes
and papayas. (… for example, pineapples, mangoes and papayas.)
So in your second sentence you have:
a variety of Alsatian wines such as pinot noir and pinot gris
This shows that (A) is a group of items to which not only (B) amd (C) belong. So, "pinot noir and pinot gris" are two kinds of wines that pertain to the group named as "(a variety of) Alsatian wines". D, E, F and G are other such wines (I don't know how many wines there are of this kind, so do not take my picture litteraly). You could also express your phrase in this way:
a variety of Alsatian wines, among which pinot noir and pinot gris.
Note: According to the explanation I quoted from the Cambridge dictionary, you should put a comma before "such as" if it introduces a list of more than one example. In your case it introduces 2 examples, so there should be a comma. However, I will not claim that this is an intransgressible rule. People do that all the time, and the comma does not really affect meaning in such a structure. It is simply considered more "neat" in writing.