The potato chip industry is upset. After 125 years of decorating hamburger and tuna fish sandwich plates and filling children's tummies, the industry thinks its product has had a bad press.

So it plans to spend $200,000 this year to get those deep fried, heavily salted, crisp, thinly sliced pieces of potato, or facsimiles thereof, off the "junk food black list" and into more school lunch boxes, government-financed school lunch programs and school vending machines.

If the potato chip industry, which is being aided in its campaign by the Fast Food Association and the Potato Board, accomplishes what it has set out to do, the potato chip will join "nuts, most fruits and olives" as "auxiliary" foods, says Ron Deutsch, a nutrition adviser to the Potato Chip Information Bureau. It is a "hard cell" campaign according to the public relations firm that is handling it, necessary because "increasing consumer awareness of nutrition is a potential problem for the industry. . . ."

Deutsch claims to have enlisted the aid of an "expert advisory panel" of six nutritionists in order to "find credible ways to talk about chips. . . that won't result in a backlash of disbelief."

They may be too late. Several nutritionists have expressed amusement ordismay at the campaign. Mary Goodwin, a nutritionist with the Montgomery County Health Department, called it "dreadful because it encourages children to eat fat, which is not in their interest. The American public is already eating too much fat and salt." Dr. Walter Mertz, head of the Department of Agriculture's Nutrition Institute, said "the danger of potato chips and other foods of that type is in over-consumption.Once in a rare while is okay."

Both Goodwin and Mertz, along with Dr. Joan Gussow, chairman of nutrition studies at Columbia University Teachers College, expressed surprise and shock at the reported presence of Dr. Mark Hegsted on the "Potato Chip Advisory Panel." Hegsted, professor of nutrition at Havard University and one of the authors of the Senate report "Dietary Goals For the United States" becomes the director of the Human Nutrition Center at USDA next month. But when asked about his role as an adviser, Hegsted said, "As far as I know there is no panel.

"We got together with Deutsch for two days and that was all. I am not on any advisory panel and I sure as hell am not interested in having them sell more potato chips, epsecially in schools."

Among the most drastic recommendations in Dietary Goals is the need for Americans to reduce substantially their consumption of both fat and salt. Thus the biggest problem with potato chips, according to nutritionists, is their extremely high fat and salt content. But Deutsch chooses to downgrade the salt and fat questions in his paper, "How Science Sees the Potato Chip," writing that on a per capita basis Americans get little salt or fat from chips.

According to Deutsch, Americans eat only .2 ounces of chips per day. This figure would be accurate if the entire population, including infants, old people and those on low-salt diets ate potato chips, but realistically the bulk of potato chips are consumed by school children, teen-agers and young adults. No one knows how many ounces of chips they consume per day, but it is not all unusual to see children making meals on large bags of chips washed down with a soft drink. Per capita consupmtion is irrelevant, critics argue.

What is relevant, Dr. Mertz points out, is what nutritionists call "the nutrient density" of potato chips. In other words, how many more potato chip calories do you have to eat in order to get the same nutrients found in an ordinary potato?

Since Deutsch devotes considerable space to the nutrients that are found in both the potato and the potato chip, particularly Vitamin C, Dr. Mertz compared the Vitamin C and caloric content of 100 grams of baked potato (about three ounces) with 100 grams of potato chips. The ordinary potato has about 80 calories and 20 milligrams (mg) of Vitamin C. That makes it a pretty good source of the vitamin.

The potato chip, on the other hand, has 16 milligrams of Vitamin C, but they are surrounded by 568 calories. "By adding so much fat (and salt)," Dr. Mertz explained, "you have greatly diluted the nutrient intake." (The entire Recommended Daily Allowance of Vitamin C is provided by a 4-ounce glass of orange juice - with 60 calories - or one cantaloupe - with 90 calories).

Deutsch argued that most people add fat to potatoes anyway by putting on butter, but a tablespoon of butter on a baked potato adds only 100 calories to make the total 180, not 568.

As for the salt content, five ounces of potato chips provide one-half of the maximum amount of salt you should have each day, according to the Dietary Goals and a number of cardiovascular specialists. Some experts believe even that level, 5 grams a day, is too high.

Dr. Ross Hume Hall, editor of a Canadian nutrition journal, Entropy Institute, believes potato chips could be called "fat chips" because the fat in them provides 60 percent of their calories. He questions the validity of the statement made by Deutsch that "the frying of chips quickly seals in certain nutrients so that the potato slices retain more of certain vitamins, especially Vitamin C."

Hall notes that "when the potato is first peeled and scrubbed with lye, the vitamin and mineral content of the skin and the layer of the potato next to it is lost." Hall asks, "if the vitamin content is retained (as the potato chips people claim) I wonder why the Roche company published ads implying that the potato chip is devoid of its original vitamins and should be fortified with Roche vitamins?"

In referring to vitamin retention, Deutsch also stated: "Laboratory studies show that fewer nutrients are lost in the potato chippers' kitchen than in some common ways of home cooking potatoes, such as peeling and boiling them." This is not true if potatoes are baked, or peeled after boiling, methods recommended by nutritionists.

None of the nutritionists disagrees with Deutsch that potato chips have more nutrients than soft drinks. But as Mertz points out, that does not put chips in the same category with nuts, fruits or even olives. According to Mertz, while "nutsare high in fat they also carry much higher amounts of micronutrients. "The oil in the nuts is all polyunsaturated. What is more, it has not been heated to high temperatures, which changes its chemical composition, causing toxic substances to form.

"You cannot compare chips with a nut," Mertz, a leading authority of micronutrients, said, "and you cannot compare them with fruits, which are lower in calories and have important pectins.

"Junk foods, fun foods. As long as people eat them just the way you use an olive in a martini."Mertz said, "it's okay, but the moment these products take on the image of a real food it becomes risky. It goes back to nutrition education. I would much rather see our children being taught to eat natural foods and look at these things are rare."

Both Hall and Goodwin find the campaign to get more potato chips into schools distressing. "School lunches," Hall said, "are more than food, they educate children as to what is supposed to be nutritionally sound practice."

Deutsch did knowledge that some questions need to be answered: "Are some teen-agers, for example, really loading their diets with potato chips, which would not be desirable," he said. "This would provide too much fat and oil."