AS the gods of haute cuisine must have planned it, the fellow in the next seat on the plane to Orlando, Fla., was a food sciences professor.

Only the day before, the food editor, down to her last recipe or something, had asked for a story on the eating habits of a sportswriter on the road.

The professor wanted to talk about Cornell University basketball, which took three seconds, and then we tackled a metaphysical/nutritional question.

"Professor, if a person spent 20 years [the question began] eating on airplanes, in stadium press boxes, in hotel coffee shops and at midnight in restaurants where they run the vacuum cleaner under your table, what sort of nutritional shape would that person be in?"

"Is this person," the professor asked, "still alive?"

Journalists are saints. Every one dresses elegantly and, if called on for a banquet toast, can fill a room with poetry. As baseball legend Dizzy Dean once said to a critic, "I know da King's English. The Queen's English, too."

But most journalists know nothing about food, except that McDonald's is the one with the golden arches.

Here is what one sportswriter had to eat in the two days after the plane reached Orlando:

Two Egg McMuffins, two orange juices, two coffees, one Quarter-Pounder with cheese, one small fries, two large Tabs, one order of nachos, one El Grande (taco, tostado, enchilada), one bag of Doritos, five beers and, on the airplane coming home, the ace of hearts melted over a bar of Ivory soap wrapped in Herschel Walker's shoelaces.

This is not an appeal for sympathy. I could have eaten better, had I wanted to, just as Dillinger could have been an accountant, had he wanted to. The food editor asked for the truth, no matter how frightening, and the truth is that sportswriters on the road fill their stomachs with potato chips, licorice sticks, beer, chili, hot dogs and catsup on blueberry muffins.

"Catsup?" the waitress said at 1 o'clock in the morning in a pancake house outside some football stadium.

"Bring the mustard, too," said Gene Roswell, a sportswriter.

Only odd people would work a journalist's odd hours under the job's odd pressures. That night after a football game, Roswell's request seemed normal enough to his buddies. Had he asked for a red wine, we might have argued for the white with muffins. We're talking odd people here, food fans.

How odd? I have eaten baby octopus at a sidewalk cafe' in Barcelona. The octopus, with its teeny-tiny tentacles, tasted just fine if you didn't think about it. I have dared the devil by eating chilled hot dogs in the RFK Stadium press box. As I ate a Milky Way, Muhammad Ali lectured me, "Sugar is poison."

Occasionally I have been taken by the collar to restaurants with table-cloths. A colleague from San Diego, Barry Lorge, remembers news events by what he ate there. You might ask, "How did Jimmy Connors play in that tournament in China?" Lorge on that event: "Claudia his wife and I went to a formal banquet for the tournament. The appetizer was snake soup and 2,000-year-old eggs, with little rice birds after."

Under Lorge's cosmopolitan guidance, I have eaten Indian curries, English puddings and Scottish beef. We spent four hours at brunch in New Orleans' Fairmont Hotel (ending with strawberry ice cream atop Pancakes Oscar, sin as sweet as it gets). For ribs, take me to Bryant's in Kansas City. For pork chops, to Pernicano's in San Diego.

Art Spander of San Francisco is my wine steward. I can tell you Stan Musial's batting average in 1948. Spander can tell you how much it rained in the south of France that year.

"We'll have the . . .," he said once to a waitress in a dreary little restaurant in dreary old Augusta, Ga. "No, wait," he said, studying the wine list. "That wasn't a good year in the Bordeaux region. Hmmm. Give us the . . ."

Spander named some wine or other, and the waitress held her pen suspended over her order pad. Dreamily, she murmured, "I've always wanted to go out with somebody like you."

I have told that story to my wife, who won't believe it because the most famous sportswriter she knows is Oscar Madison of TV's "The Odd Couple." In the movie version, Oscar makes sandwiches for his poker buddies on a day so hot he's sweating bullets. Oscar sticks the sandwiches under his arms to deliver them.

"You," my wife says, "are Oscar."

I love hot hot dogs at the ballpark. Give me crab cakes at Memorial Stadium. Dish up a bowl of chili in Texas Stadium.

Okay, I hear you. He is Oscar. Well, against the possibility that oddness would overwhelm me, I long ago found a way to maintain my nutritional sanity on the road.

I search for the perfect ham-and-cheese omelet.

Truman Capote carries paperweights when he travels. He sets them on the desk in his hotel room. It gives him a sense of home, he says. It is an anchor against the storm of disorientation that buffets a traveling person. My paperweights are omelets, so to speak.

America's best ham-and-cheese omelet is served in the Cafe Roma of Caesars Palace in Las Vegas. It is a three-egger ever so fluffy, with golden cheese melting around ham finely ground.

In Denver, St. Louis, Louisville, Richmond, Seattle (and other places), I have sent a ham-and-cheese omelet back to the kitchen because it came with no ham.

In the Tulsa airport, I asked a waitress, "Where's the cheese?"

"You wanted cheese?"

"It's a ham-and-cheese omelet."

She left her station for 10 seconds and returned with a slice of American cheese, which she draped over the omelet.

"There," she said.

One other food-on-the-road note: McDonald's charged 25 cents for a cheeseburger in the late-'50s in Illinois. On my trip last week to New York, the Statler Hotel's coffee shop sold me a cheeseburger for $9.75.