JUST AS only one wine, the champagne from the Champagne district of France, is really champagne, only one cheese, Parmigiano-Reggiano, can legally be called Parmesan. Parmigiano-Reggiano, the hard granular cheese we call Parmesan, has been made by hand in the area around Parma, Italy, for more than 700 years and this noble product of the cheese-maker's art bears little resemblance to the cornmeal-like cheese sold here as 100 percent grated Parmesan.

Under Italian law the cheese called Parmigiano-Reggiano must come from the milk produced in the zona tipica a territory which comprises the provinces of Parma, Reggio Emilia, Modena, Mantua on the right bank of the River Po and Bologna on the left bank of the River Reno. The hard grating cheese made outside this area is called granna and is often sold here as Parmesan. Authentic Parmesan has the words Parmigiano-Reggiano imprinted all the way around the rind of the cheese.

Not only is freshly grated Parmigiano-Reggiano an essential part of Italian cooking, it is also prized as a table cheese. Pale yellow to golden in color, it has a full-bodied yet delicate flavor that lingers on the palate. Its interior is filled with barely visible holes and it flakes when pulled apart.

During a recent trip to Italy I visited Parma and saw the ancient artisan process of cheese-making.

The cheese is produced only between April 1 and Nov. 11 when the cows are fed fresh grasses. In this part of Italy cows are almost always kept in cowsheds. The grass is cultivated, harvested and brought to the barn. Cows do not graze because their hooves damage the clay-like soil of the region.

During the winter months cheese-making continues but since the cows are fed silage a cheese with a different flavor is produced. The winter cheese, Vernengo, has the same drum shape of Parmigiano-Reggiano, but it is made with pasteurized milk whereas Parmigiano-Reggiano is made with raw milk.

The making of the cheese is a cooperative effort. A group of farmers will employ a cheese-maker and form a cheese dairy where they bring their milk. There are approximately 1,200 cheese-making dairies in the region and they produce almost 2 million 60-pound cheeses a year.

The cheese-making process begins with the arrival of the evening milk, which is tasted every day to be certain of its quality and is poured into flat, rectangular, stainless steel skimming trays to rest overnight. The cream is skimmed off to be used in making butter. The morning whole milk is added to the evening skim milk and a fermenting whey, a residual from the previous batch, is added.

The mixture is heated in copper cauldrons, stirred slowly and then the heat turned off and rennet added. Coagulation of the curd from the whey occurs with 12 to 14 minutes. The curd is broken up by hand with a tool called a spino or thorn bush, a long wooden broom-like stick with a circular metal head; then the mixture is slowly heated again. After the heat is turned off the cheese granules go to the bottom of the cauldron where they form a mass again.

Using a large square of natural hemp cloth, the cheese-maker and his helper remove the mass from the cauldron, cut it in half and put it into wooden molds. rThe cheese is then pressed to remove any remaining whey and imprinted with the words Parmigiano Reggiano.

In three days the cheese is removed from the mold and put into a salt solution to soak for three weeks. During this process salt will enter the cheese body and any raw bacteria will be killed. Water continues to be released from the cheese during these steps. Each cheese is also imprinted with the cheese-maker's index number and the month and year when it was made.

Then the cheese is put into a storehouse to begin the long aging process. At regular intervals the cheese is turned over and the dust brushed off. At the end of the year the season's crop of cheese is transferred to a large commercial storage house to complete at least 18 months of aging. These complexes continue to age the cheese, testing it at intervals to ensure that the aging process is continuing properly. It's during this period that the cheese receives its first mechanical handling. A machine moves up and down the long aisles, 15 layers deep with cheeses, turning and dusting them.

Parmigiano-Reggiano is so prized in Italy, where it sells for about $5 to $6 a pound, that only 4 percent of it is exported worldwide. But real Parmesan is available here and it's worth the search.

The price of Parmigiano-Reggiano ranges locally from $7.90 to $9.99 per pound. That compares with $5.07 for Kraft grated Parmesan in the 3-ounce size. The Stella brand five-ounce, pie-shaped Parmesan wedge is $5.92 per pound. Imported Argentinian Parmesan is approximately $6.99 per pound and Italian granna about $8.25.

Some of the area stores that sell Parmigiano-Reggiano are: Cheese & Bottle, 4508 Lee Hwy., Arlington; The Cheese Villa, 6653-B Old Dominion Dr., McLean; Eagle Wine and Cheese, 3345 M St. NW; The Wine & Cheese Shop, 1413 Wisconsin Ave. NW; Aspen Hill Wine, Beer & Cheese, 13745 Connecticut Ave., Wheaton; Potomac Wine & Cheese Shop, 10114 River Rd., Potomac; Silver Spring Cheese & Wine, 8746 Georgia Ave., Silver Spring.