Reading a package of Italian rice can be confusing until you have the terminology sorted out. The package tells us two things about the rice inside: its grade and its variety.
Size and Grade
Rice, like eggs, comes in different sizes and grades. Italian rice is graded according to length (short or long), shape (round or oval) and size (small, medium or large), as well as wholeness (broken grains are appropriately downgraded). What results are the following grades, which are marked on the packages.
*Comune or originario: The cheapest, most basic rice, typically short and round. It is used mostly for soups and desserts, never risotto. The rice most often seen with this grade is the Balilla variety. It cooks faster than other grades.
*Semifino: This grade, of medium length, maintains some firmness when cooked. Risotto can be made with a semifino grade, although semifino is better employed in soups. The rice variety most often seen with a semifino grade is Maratelli.
*Fino: Here we arrive at genuinely fine rice, as the name says. The grains are relatively long and large, and they taper at the tips, creating an oval shape. Fino-grade rice remains firm when cooked. Several varieties are commonly graded fino, including Vialone Nano, Razza 77, San Andrea and Baldo.
*Superfino: Just what you'd expect, the top of the line. This grade represents the fattest, largest grains. Superfino is the province of the two best risotto varieties, Carnaroli and Arborio. They take the longest to cook, as they can absorb more liquid than any of the others while still remaining firm. I have never seen Arborio and Carnaroli graded anything other than superfino.
Italian Rice Varieties
As is well known, rice is divided into short-, medium- and long-grain varieties. But within that broad categorization are an estimated 8,000 varieties or strains of rice. The vast majority of these strains are hybrids, created by rice growers to improve yields or disease resistance or to deliver enhanced textural or flavor qualities.
So it is with the various Italian rices. There are noticeable differences among the Italian rice varieties. These differences are not a matter of flavor but rather of size, creaminess (when cooked) and texture. All Italian rice varieties are strains of a thick, short-grained rice called japonica, botanically, Oryza sativa japonica. (The long-grain rice popular in the United States is Oryza sativa indica.)
New hybrids are forever under development, which has led to what might be called (using wine jargon), varietal rices. They take the commercial name of the hybrid. They don't, to my palate, taste different. They do, however, offer noticeably different textures and different degrees of creaminess when cooked. Which variety you use will make a difference, although not a critical one. All of the following can be used successfully (and interchangeably) for risotto.
*Carnaroli: This is the supreme variety for risotto and the one preferred by every restaurant chef I talked to in Piedmont. It has the largest grain of any of the rice varieties, retains a rewarding "bite" even when fully cooked and, best of all, rewards the cook with a satiny creaminess while keeping a firm mass.
Carnaroli is an old variety that almost went out of commercial existence because it yields less than newer strains. It has been revived in recent years and now is in widespread production, thanks to the unstinting celebration of its qualities by many Northern Italian chefs. The demand for Carnaroli is such that dark rumors percolate that some rice sold as Carnaroli really isn't. Unfortunately, it is impossible to distinguish raw Carnaroli from another good variety such as Arborio until you cook it. Then the sheer size and plumpness of cooked Carnaroli reveals its authenticity.
Carnaroli rice is not as commonly available as Arborio rice, but it can be mail-ordered. One source is Corti Brothers, 5810 Folsom Blvd., Sacramento, CA 95819; (916) 736-3800.
*Arborio: The most famous of all Italian rice varieties, it takes its name from the Piedmontese village of Arborio, which lies near the famous Gattinara wine zone. Like Carnaroli, Arborio can absorb a lot of liquid while still retaining a firmness when fully cooked. It also is generous in size. This is the "standard" risotto rice and with good reason: It works wonderfully well. It is widely available.
*Baldo: You don't see Baldo much outside of Italy. Derived from the Arborio strain, it is a recent innovation that offers quite a bit of creaminess but not as much firmness as either Arborio or, especially, Carnaroli. I don't think it's worth going out of your way for.
*Vialone Nano: An old variety more appreciated in Lombardy and Veneto than in Piedmont. Vialone Nano probably expands more than any other variety, tripling in size when cooked. However, it becomes slightly mushy in the process, which makes it ideal for the lighter, soupier style of risotto but less good for achieving Piedmont's preferred density. Its absorptive capacity, though, makes it a terrific choice for seafood risotti, the taste of which is better infused in Vialone Nano, thanks to its flavor-welcoming texture.
Other Italian rice varieties include Roma, Razza 77, Maratelli, San Andrea, Padano and Ballila.