All critics have one cherished artwork they greet each time they visit their local gallery.

At the National Gallery of Art, I adore Raphael's great Alba Madonna. But I've been known to pass her by.

I seek out Titian's famous portrait of Ranuccio Farnese -- on at least every other visit.

The one work of art I never miss is on less obvious display, down on the lowest level of the East Building, by I.M. Pei's cascade. I'll sometimes visit the gallery on the pretense of seeing something else -- maybe a show of Vermeer's greatest hits or something equally banal -- knowing that I'll also get to run downstairs to savor my secret love.

There's no wall label giving this work's author or date, but I know its medium: Italian ice cream, available in 19 flavors. The gelato at the National Gallery's espresso bar is one of the museum's hidden gems.

Like other art historians who've spent time in Italy, I miss gelato almost as much as any of the country's more permanent artistic treasures. That's why I recently decided that it deserved the close, professional consideration I give to other works of art.

Just this Thursday, I arranged a "private viewing" of the gallery's gelato holdings and invited along fellow connoisseur Eleonora Luciano, assistant curator of sculpture. Luciano was born and grew up in Italy -- first in the north, then in the far south -- so would be sure to balance any North American prejudices I might bring to my critique. (You can tell she's a real Italian because a passion for gelato apparently has no effect on a slim waist, and because her linen skirt and crisply tailored blazer are classically "breeteesh," as they say in Italy.) The National Gallery's food "curator" -- Daniel Karsevar, of Restaurant Associates, the company contracted to run the museum's restaurant operations -- supplied the exhibits: a table full of cups of freshly scooped gelato. (It has been salad for dinner ever since.)

First, vanilla -- the primed "canvas," as it were, behind many works of frozen art. The National Gallery's version was much softer, smoother, more voluptuous than any American ice cream could be -- it had none of the hard edges of a Norman Rockwell-style scoop, or his excess of sweetness and fat.

We tried other artistic parallels. Michelangelo seemed at first a likely match, since vanilla is at gelato's heart the way the Florentine is at the root of any art that followed after him. But that wouldn't do -- the gallery's vanilla was too mellow, almost too dissolute, to come from that master's firm hand. Raphael's softness came closer -- but was still too classically poised for a vanilla that had an undertone of real flamboyance. Then we got it: Tiepolo. The gallery's pungent "Bourbon vanilla" (the best beans once came from the French "Bourbon" islands in the Indian Ocean) was like one of Tiepolo's rococo clouds: White at first glance, but with a dozen other tones lurking underneath to give it heft.

Peach gelato was much easier to match to an Old Master: Giovanni Bellini. The peach cocktail named after him made this an almost cliched choice, of course. But we couldn't forget the peachy, golden light of his greatest pictures (that sunset in the National Gallery's great "Feast of the Gods," for instance) and the comfortable, quiet sweetness in his Renaissance madonnas, just like the flavor of the peach gelato we had at hand -- not as intense as other options, but exquisitely comforting.

Luciano, the sculpture expert, made the call on the gallery's chocolate gelato: Bernini would be its patron saint. It was slightly firmer than the other gelati, richer and more baroque in flavor profile. It was also an obvious crowd-pleaser that still offered depths for further contemplation. Extravagant and carefully contrived, at once.

And then there were the flavors with a more modern aesthetic attitude: cinnamon, which seemed to have a cubist spice to it, and banana-blueberry, which had an almost pop art touch. Betty Edwards, who has long run the gelato machines at the gallery, talks of other flavors they've dreamed up that lack Italian precedents: pumpkin, served around Thanksgiving, and eggnog served for the holidays alongside her own invention, candy-cane gelato.

Albert Lukas, executive chef at the gallery, says he even tried to take the art form to the radical fringe. Black truffle gelato, however, wasn't as good as he had hoped.

After our aesthetic marathon, Luciano and I agreed that the assembled tastes and textures brought back crisp memories of Italy. (We both missed the much smaller servings available there, however. They allow patrons to take tiny gelato hits, and then repeat them with other flavors, instead of consuming a super-size single taste. Karsevar heard our complaint: He says that from now on, the staff won't balk if you ask for extra flavors in the $2.75 "single-flavor" cup.)

But, for all the pleasure that our tasting brought, we hadn't quite encountered any great masterpieces of the gelataio's art. The National Gallery's gelato is made fresh daily with whole milk and a dollop of cream, as it should be. (Gelato hovers at 6 percent butterfat, compared with 20 percent or more for American ice cream. The fruit flavors, properly known as "sorbetti," have almost no fat at all.) But, like all but a tiny handful of gelati, even in Italy, the flavoring components come from prepackaged "compounds," imported in this case from a firm in Turin. Edwards can't build a new taste from the bottom up; she can only blend or tweak what comes from Italy by adding extra fruit or a new ingredient or two. And the texture, again as often in Italy, depends on mixing in a mysterious powder that can't have been around in gelato's early days. (At rival gelateria Gelatissimo, some blocks west of the gallery in the food court of the Ronald Reagan Building, owner Stelvio Pacchini says that he adds similar imported flavors to a base he makes from scratch. But for all the wonderfully authentic look and feel of his establishment -- his display cases were shipped direct from Italy four years ago; he moved from Florence only six years before that, when he was 61 -- his gelato doesn't quite measure up to what the gallery can offer.)

Maybe, coming fresh to a foreign tradition, Lukas and Edwards shouldn't be expected to live up to grand models like Tiepolo, Bellini and Bernini. They're at a happy second level, filled by great unknowns like Bacchiacca, Beccafumi and Schiavone.

They're undervalued makers riffing on the greatest masters' innovations, providing heaps of pleasure as they go.

Cherry gelato at the National Gallery of Art, one of the museum's hidden gems.Italian-style gelati of many flavors, some classic, some not, sit ready to be savored at the National Gallery of Art.A freshly scooped serving of gelato makes its way to a customer at the National Gallery. In Italy the servings are smaller than those in America.