The intrepid science of food engineering reached an improbable juncture at UC Berkeley recently when food scientist Benito de Lumen began designing a bean devoid of that disconcerting attribute for which the legume is best known.
De Lumen's quest for a flatulence-free frijole is part of a booming field of food research that has already produced such seeming gustatory oxymorons as low-cholesterol eggs, dietetic chocolate ice cream and high-fiber hamburger buns.
The ability of scientists to design foods without their old drawbacks offers more than a promise of guilt-free gluttony: It holds out hope of controlling such threats as heart disease and cancer, linked to excesses in the American diet.
But whether engineered food will fulfill that potential remains to be seen. Some nutritionists have doubts. They warn that such foods, consumed immoderately, could lead to new nutritional problems on a par with those they are intended to avert.
"One could envision in the next 10 years that it would be possible to engineer any food that we eat that would be almost devoid of any nutritional content except for fiber, vitamins and minerals," says Theodore Labuza, a food scientist at the University of Minnesota.
"Now it's very possible that the incredulous consumer . . . would begin eating these products solely. So they would end up not with vitamin or mineral deficiencies but . . . protein deficiencies and energy deficiencies."
What are the benefits and drawbacks of engineered foods? It is almost impossible to generalize. Some have no known shortcomings, but others may--especially if they shoulder out more healthful foods from the American diet, nutritionists say.
Low-fat and skim milk, for example, have no down-side. They offer all the benefits of whole milk without the fat and calories. Like modified mozzarella and ricotta cheese, they offer more protein, vitamins and calcium than the products they are designed to replace.
But fat substitutes don't necessarily work that way. One, sucrose polyester, is not even digested by the body. That means that it has no calories or cholesterol, but that it also offers none of the essential fatty acids people need for growth and maintenance of their skin.
Such a shortcoming matters little if the product is used in moderation. What concerns some nutritionists is that it might be consumed in excess, drawing eaters towards foods that have suddenly been rendered innocuous and away from more fortifying alternatives.
"If we have both artificial sweeteners and fats, will people eat more cake?" wonders Audrey Cross, a nutritionist and lawyer at Columbia University School of Public Health. "And if they do, what will they be leaving out of their diet that they were eating before?"
Not only might people eat less fruit, but they actually may eat more sugar as well. It remains to be proven that substitutes for foods such as fats and sugar can accomplish what promoters say they can--that is, that they can reduce consumption of the real thing to recommended levels by substituting a less harmful alternative.
Per capita consumption of sugars has risen steadily since the introduction of artificial sweeteners, health experts point out. Artificial-sweetener use has also soared, leading some experts to wonder whether sweeteners stimulate some people's appetite for sugar.
Obesity, too, has continued to increase.
"Thus far, there is no evidence that the proliferation of low-calorie foods, analogs and ingredients has affected the status of obesity in the United States," the Institute of Food Technologists, a professional scientific society, reported recently. "National statistics . . . show an increase in the prevalence of obesity, certainly no decrease."
The first federal health and nutrition survey, conducted between 1971 and 1974, found that 28.8 million American adults were obese, 8.4 million of them severely. The second survey, done between 1976 and 1980, found that the numbers had risen to 34 million and 13 million, respectively.
Part of the impetus for redesigning foods arises out of the growing evidence that diet plays a significant role in the development of chronic diseases--specifically, diseases such as hypertension, atherosclerosis, diabetes, liver disease and cancer of the breast.
Research indicates that one's risk of contracting such diseases can be controlled by selecting carefully the foods one eats. Numerous scientific panels have urged Americans to eat less food heavy in fat, and more high-fiber foods such as vegetables and fruits.
"Engineering of foods, I think, is terrific," says Wayne Bidlack, an associate professor of pharmacology and nutrition at the University of Southern California. "We can decide what nutrients need to be delivered where, and design products for whatever is lacking."