Tasting through Robert Mondavi's portfolio continues to reinforce my impression that this winery is undeniably the spiritual and qualitative leader of that sector of the California wine industry dedicated to producing world-class wines. What is so admirable about the entire Mondavi operation is that they continue to push their wines to higher and higher qualitative levels. Their nearly obsessive pursuit of bottling the wines with no manipulation has led to the majority of Mondavi's white wines being bottled without filtration - an extraordinary testament to their commitment to natural wines and superb quality. Mondavi has also inaugurated a line-up of Italian-inspired varietals (Barbera, Sangiovese, Pinot Grigio, Malvasia, and Tocai) in designer bottles. While the quality is good, those products have not yet hit the heights of the firm's other wines. Rest assured, that will change.Mondavi's Merlot program has not yet reached the heights of their Fume Blanc, Chardonnay, and Cabernet Sauvignon offerings, but the winery is on the right track. Much more interesting, riper, and better-balanced than the 1992 is the 1993 Merlot. It reveals more of a chocolatey, black-cherry component, and a more complete mouthfeel without the 1992's tough, tannic finish. The fruit is sweeter, more concentrated, and, as a result, more interesting. Drink the 1993 Merlot over the next 7-8 years. All things considered, there is plenty to be excited about at the Robert Mondavi winery. Tel. (800)-MONDAVI; Fax (707) 963-1007.