Interactions Between Wine & Food Acidity

The basic rule of thumb is that food acidity levels should be less than or equal to wine acidity.  When high-acid foods are matched with high-acid wines, the acidities tend to cancel each other out, allowing the fruit and sweetness in the wine to come through.  Matching acid levels can also let subtle food flavors become more prominent in dishes, without the wine accompaniment, they might taste sour at first bite.