The "Italian" symphony has always been my go-to for background wine tasting music. Along with the "Scottish" and "Reformation" symphonies as well as Mendelssohn's overtures. Also, Rossini and Offenbach overtures. The Band, Astral Weeks, Moondance, Layla and Other Assorted Love Songs, and mixes of Joe Cocker have made several appearances as well. For whatever reason, Sinatra also plays well as background music during a wine tasting, to me.
Mendelssohn and Joe Cocker are rarely mentioned in the same paragraph.