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.As I stated earlier, Mondavi has launched an Italian varietal campaign, with good rather than sublime results. The finest of recent offerings are two white wines, the wonderfully crisp, delicate, dry, perfumed, fruity 1994 Tocai Friulano, and the heavenly-scented (spring flowers and tropical fruits), off-dry, outstanding 1994 Malvasia Bianco. The latter wine should be drunk as an aperitif, or following a meal as it possesses residual sugar. But, wow! What a knock-out nose and personality this wine displays. Both wines should be consumed before summer, 1996 for their delectable fruit and aromatics. All things considered, there is plenty to be excited about at the Robert Mondavi winery. Tel. (800)-MONDAVI; Fax (707) 963-1007.