The Bordeaux Betrayal by Ellen Crosbie

 This is one of the earlier books from the excellent Virginia Vineyards mystery series. Lucie is holding a fundraising auction for a local charity at her vineyard. One of her neighbors donates a bottle of wine with ties to both Thomas Jefferson and George Washington. Then the man who donated the wine wants it back.  A couple of people end of dead and Lucie is in the thick of things once more. 

There's always a lot of interesting winemaking lore and history in these books, along with the mysteries, which is another good reason to read them.