Chemist J. Michael Gould has reversed the logic of cupcakes. With his invention of "fluffy cellulose" -- a no-calorie supplement made from straw, citrus pulp or sugar beets -- the U.S. Department of Agriculture researcher can turn a Twinkie into a high-fiber, low-calorie food -- without altering its flavor.

Donald Beitz, a professor of animal science and biochemistry at Iowa State University, envisions a day when "please pass the cholesterol reductase" will become a standard dinner table request. Beitz is working to develop an enzyme that could be sprinkled on foods to reduce their cholesterol.

Procter & Gamble recently submitted a petition to the Food and Drug Administration for approval of sucrose polyester, a fat derived from sugar and edible oils. Because it passes through the body unabsorbed, it contributes no fat, cholesterol or calories to the diet. If approved, olestra -- as P&G calls its compound -- could become as widespread in the food supply as NutraSweet.

In laboratories all across the country, government scientists, university researchers and food companies are engineering foods that may be the edible equivalent of having it all -- to indulge without gaining weight, to eat fat-laden and cholesterol-loaded foods without worrying about heart disease, to guiltlessly choose chocolate cake as a fiber source over prunes or beans.

"You're never going to convince people to only eat foods that are good for them," said USDA's Gould, much to the likely chagrin of nutritionists and health professionals. Instead, Gould believes, "We have to make foods to fit people's taste preferences."

Beneath the nirvana such products might bring, however, are broader questions about their impact on the food supply. How far should science go to manipulate real food? How necessary or safe are some of these ingredients? What could be the effect of a combination of them in a single product? And will overzealous food companies use medical findings that lack consensus to make grandiose health claims for their "wonder" goods?

Already, manufacturers have created controversy in the health community by formulating products such as calcium-fortified orange juice and soft drinks and competing in high-fiber cereal wars. While health experts are generally recommending that the public consume more calcium and fiber, some are worried about indiscriminate fortification of the food supply with these nutrients and question whether some of the products are simply being promoted for marketing purposes.

Jack Doyle, director of the agricultural resources project for the Environmental Policy Institute, believes that engineered foods do not bode well for consumers. Such processes not only increase the price and mystification of food, he said, but when food is developed in the confines of a fermentation tank or petri dish, it weakens consumer input. "It leaves the high priest in the lab in control," rather than the marketplace, said Doyle, who is suspicious of taking scientists' "word for it {safety}."

Sanford Miller, outgoing director of the Food and Drug Administration's Center for Food Safety and Applied Nutrition, believes that such foods and food processing methods have "enormous potential for both good and bad."

Miller said that engineered fat-free products may afford people with special dietetic problems their first opportunity to "enjoy French pastry." On the other side of the coin, Miller said, non-caloric foods might be dangerous for individuals with eating disorders, who could gorge to their heart's content and not gain weight. Miller is also concerned about feeding these types of foods to growing children.

Nevertheless, Miller said that although a lot of research still needs to be done, consumers should not be suspicious of new technology. Miller said that he suspects that people felt the same way about airplanes and birth control pills before they became available -- as did the first cave man who cooked raw meat on a fire.

Many of the research projects to develop these products are being funded by industry and commodity groups that would like to see increased consumption of their goods. Others, such as the USDA's fluffy cellulose, are attractive because the product has the potential to maximize use of parts of raw agricultural ingredients that would otherwise be wasted.

Some of the ingredients could ultimately be mass produced via genetic engineering. Currently, much of the agricultural research in biotechnology is centering on increasing plant yields and reducing processing costs, but the science could someday be applied to giving cows genes to produce lowfat milk, for instance.

The following examples of engineered foods and food additives are in various stages of development:

Spreadable lowfat butter. While there are already a plethora of margarines and margarine imitations in supermarket refrigerator cases, the dairy industry is fighting back with its own alternative.

Scientists at Dairy Research Inc. (DRINC), a developmental arm of the National Dairy Promotion & Research Board, are working on an all-dairy product that is 35 to 40 percent lower in fat, cholesterol and calories than regular butter and spreads like tub margarine right out of the refrigerator.

Ann Cassela, a project leader with DRINC, said that the new butter is made from cream, milk and a "touch of beta-carotene" and is manufactured using an "updated technology" called ultrafiltration. The finished product has less fat because it has more water left after processing than does regular butter, Cassela said.

Currently, spreadable butter is being "scaled up" by a large dairy in the Midwest, according to Cassela, who predicts that it will be on supermarket shelves in about a year.

Cholesterol-free eggs, meat and dairy products. With a grant from the Wisconsin Milk Marketing Board, Beitz from Iowa State hopes to change the nature of cholesterol in food so that it can't be absorbed in the body.

To do this, Beitz is attempting to grow the bacteria that naturally occur in the large intestine which convert cholesterol to coprastinol, a steroid that is poorly absorbed. Once isolated, the enzymes produced by the bacteria could then be used to treat dairy products or meat, converting their cholesterol to coprastinol before they are consumed.

While Beitz and his colleagues are at the early stages of their work, he dreams about the future applications should it be successful. For instance, Beitz said that someday egg packing plants could be equipped with fast-spinning needles containing the cholesterol-reducing enzyme that would be inserted into the shells as they move along the conveyor belt.

At the University of Wisconsin at Madison and the Phasex Corporation in Lawrence, Mass., researchers are at more advanced stages in cholesterol removal from foods. The method being used, called superfluid critical extraction, begins by compressing carbon dioxide to a temperature at which it behaves somewhere between a gas and a liquid. A freeze-dried or spray-dried food is then heated to a specified temperature and the compressed CO

is run through the vessel, dissolving a substantial portion of the cholesterol.

According to Robert Bradley at the University of Wisconsin food science department, "many food companies" have expressed interest in the process, which is currently in patent negotiations. Bradley predicts that products such as low-cholesterol ice cream, cheese and beef tallow could be on the market in a year or more. As for the saturated fat in these products, he said that the technology already exists for lowering fat.

High-protein food bars and meatless meat pies. Dave Dreisker, vice president of the Provesta Corp., a subsidiary of Phillips Petroleum, would like to see "everyone munching on a Meal On the Go" while stuck in morning rush hour traffic. Two weeks ago, Provesta started test marketing its new food bar in northeastern Oklahoma. Made with Provesteen, a high-protein yeast grown in fermentation tanks, the bar is combined with ingredients such as wheat, bran and pineapple, and is designed as a meal substitute rather than a snack. Dreisker said it looks similar to an oatmeal cookie.

The race is on to develop food products from these single-cell proteins (SCP), as they have been generically called. Using a similar fermentation technology, two British companies -- Ranks, Hovis and MacDougall and Imperial Chemical Industries (ICI) -- are producing a material that can assume the texture of beef, chicken -- or even potato chips.

The material, a fungus, is then combined with flavorings, spices or breading to simulate the taste of the desired final product. By enhancing or suppressing the texture, the fungus could resemble a food such as a potato chip, according to Stuart Pape, an attorney who is representing RHM in this country. High in fiber, low in fat, sodium and cholesterol and with a protein profile superior to soy, RHM's protein was approved for use in Britain in October of 1985 and is currently being sold in frozen pasties (meat pies). The company filed a petition last year with the FDA for approval to use in frozen entrees here.

High-fiber white bread, etc. Gould calls the USDA's fluffy cellulose "invisible fiber" because it does not have the coarse or gritty texture of regular fiber. The ingredient could be used to replace part of the flour in baked goods; Gould said that consumer panels couldn't tell the difference between a control cake and a cake in which fluffy cellulose was substituted for 40 percent of the flour.

Fluffy cellulose is being pursued "vigorously" by a number of companies, according to Gould. The process of making the product, which involves treating a fiber source with a diluted solution of hydrogen peroxide, has already been licensed to four firms (Dupont, Interox American, Food and Energy Inc., Southwest Bioenergy) and the food formulation of the product is currently being patented, Gould said.

New non-caloric sweeteners. Currently, the FDA has four non-caloric sweeteners under active consideration: acesulfame K, sucrolose, alitame and cyclamate. Lactitol, a caloric sugar substitute, is also being reviewed by the agency.

Of all the sweeteners, acesulfame K presently looks the most promising, according to Joan Patton, spokesperson for the Calorie Control Council. In fact, Patton said that there are indications from FDA and the manufacturer of the product that approval is "imminent."

Derived from acetic acid, acesulfame K is 200 times sweeter than sugar and has already been approved for use in 17 other countries, according to Patton. The petition for its approval, submitted in 1982 by a West German company with a U.S. office, asks for use only in dry goods.

Sucrolose, submitted for approval by Johnson and Johnson in early February, is derived from sugar but has no calories, according to Edwin Watson, spokesperson for the company. Sucrolose -- 600 times sweeter than sugar -- maintains its sweetness when stored for long periods of time and does not break down during baking, according to Watson.

Alitame -- a combination of two amino acids -- is similar to aspartame because it contains L-aspartic acid, but contains D-alanine instead of L-phenylalanine. L-phenylalanine makes aspartame off limits to phenylketonurics, who cannot metabolize the amino acid. The petition for alitame was submitted by Pfizer, a multinational pharmaceutical and agricultural chemicals company, which also makes polydextrose, a reduced-calorie bulking agent approved by the FDA in 1981 that is currently being used in a number of low-calorie foods.

Cyclamate dominated the artificial sweetener market in the 1960s but was banned in 1970 when tests showed that it caused cancer in laboratory animals fed with a mixture of cyclamates and saccharin. The company that manufactures cyclamate, Abbott Laboratories, petitioned the FDA in 1982 to remarket the sweetener.

Fat-free fats. Of all the developments, sucrose polyester -- or olestra -- has been making the biggest headlines since Procter & Gamble's petition for its approval was filed with the FDA last month. Discovered by a P&G researcher in the 1960s, sucrose polyester has been under development for more than 20 years, according to company spokesperson Sue Hale.

What makes the substance particularly revolutionary is that it has been shown to actually lower serum cholesterol, although Hale said more research still needs to be done. Olestra would be positioned as a calorie-free fat replacement, not a cholesterol-lowering product, Hale said.

The FDA will have to investigate, among other things, whether olestra interferes with the absorption of certain fat-soluble vitamins. Hale said "it could have a mild effect on vitamin E" but that the company has supplemented the compound with the vitamin.

P&G's petition seeks usage of olestra as a partial substitution in its cooking oils (Puritan and Crisco) and for salted snack foods. The company also sells a lot of cooking oils to fast food establishments and restaurants, which would also be potential markets.