Anxiety attack on Aisle 2 at the A & P: Snow Benedict was too late. Fellow "Coke-a-holics" had beaten her to it. There were only a few bottles of the Real Thing left. Only the new, reconstituted Coca-Cola sat staring at her from the shelf, its arrogant yellow sticker proclaiming "NEW TASTE!"

"Oh, no!" gasped Benedict, 41, rounding the corner last night with her cart, a 9-year-old Little Leaguer in tow. Her blue eyes glazed over.

"I live on Cokes," she said. "A liter a day. That's all I drink, water and Coke. And when I want one, I want the Real Thing, with sugar and caffeine, the original formula. At home, no one drinks out of my bottle. Why? 'Cause it's my bottle! It's my fix!"

Coca-Cola always comes at the top of her shopping list, after milk for two kids. It has vaporized rust on her car, cured stomach upset, boosted marital bliss and chased away gremlins after party time.

"Nothing makes me feel better after a hangover," Benedict says, wondering if the new Coke will have similar properties. It has played the role of teddy bear and Linus' blanket. Will she ever be happy again? Will she ever win again at tennis? She won't play without one, or two. And when teammates forgot her ration the other day, she raced out to buy some. She won.

"I'm a Coke-a-holic," she says with pride.

Now, Coca-Cola has changed its secret formula.

"It's a sacrilege," says the petite real estate saleswoman. "It's like they're trying to change the image of motherhood."

Unfortunately for devotees like Benedict, they were outvoted in market data sifted by Coke's marketing gurus. In a blind taste test, consumers opted for the "new taste" 55-45, say officials. When they were told which was which, the margin leaped to 61-39.

"A landslide," pronounced Donald R. Keough, president and chief operating officer of the Coca-Cola Co., which is headquartered in Atlanta. Yet, an informal test conducted by local reporters at the Varsity, billed as the world's largest drive-in, found grumps galore. And the grumps were back today.

"I won't ever drink another Coca-Cola," fumed businessman Walter Green, 31, wheeling off the interstate to feast on legendary chili dogs and fried onion rings. "They broke tradition. I'm a Dr. Pepper man from here on out."

Come Wednesday, the Varsity drive-in, the world's largest retail dispenser of the Real Thing (400 gallons a week), begins hawking what some are calling the "unreal thing." Patrons had heard the new Coke would be sweeter and "smoother," as officials put it: more like Pepsi.

"Drinking Pepsi," grimaced Scott Hunter, 20, a Georgia Tech student, "is like drinking pure sugar. I like the way Coke tears your guts out on the way down. Can't stand Pepsi. I don't know what I'll drink now."

To Coca-Cola, with all its history and tradition, change comes hard.

"Atlanta has had a love affair with Coca-Cola for years," says Wilbur G. Kurtz Jr., 72, retired archivist for the company that boasts 400 million servings a day worldwide and $7.4 billion in yearly sales.

"It was Coca-Cola, Bobby Jones and Margaret Mitchell's 'Gone With the Wind,' " he says. "Those are the three jewels in our crown."

Adds Franklin Garrett, official city historian: "When it comes to quenching thirst and creating wealth, nothing means more to Atlanta than Coca-Cola." But the idea of a new formula gives him pause. "If it ain't broke, why fix it? I don't think all is lost, but the old stuff suited me. Nowadays, there's a tendency to want to fix everything. But, I guess, there's nothing as permanent as change."

Coke has become the stuff of legend, sacred to Atlantans. It calmed colicky babies. Dr. Sanford Matthews 59, a pediatrician here, doesn't hesitate to prescribe it for children with the "throw-ups."

"It has some mysterious, calming effect," he marvels.

Archivist Kurtz says that in World War II, one soldier wrote his mother, begging for a 6 1/2-ounce bottle. It arrived at his Pacific base: the only Coke on the island. He auctioned it off. With poker pots aplenty, and nothing to buy, it sold for $4,800, says Kurtz. The GI mailed the money home and used it later for college.

Says Big Star store manager Howard Horne, 51: "We've had quite a few customers who can't understand why it worked for 99 years and, all of a sudden, they want to change it."

He says some drove up and filled trunks with the old stuff. A few confessed they aimed to mix it with something stronger.

"They didn't like the idea of bourbon and Pepsi," he adds.

Some wonder if the company aims to reintroduce the Real Thing all over again, with much hoopla, down the line. Snow Benedict prays Coke will consider marketing the old formula via gourmet shops.

"I'll pay a premium," she says.