The Future of Biotechnology in Food Processing

Susan K. Harlander, assistant professor, Department of Food Science and Nutrition, University of Minnesota, St. Paul, and Richard G. Garner, food scientist, Cooperative State Research Service.

By the year 2000 the worldwide market for biotechnology-derived food and agricultural products could be valued at tens to hundreds of billions of dollars. The results of the rapid pace of biological research since 1970 indicate that we are only scratching the surface of the potential.

We define biotechnology broadly, as the use of biological systems, including micro-organisms or components produced by micro-organisms, in industrial processes. Micro-organisms have been used in food preparation for centuries to preserve and transform raw agricultural commodities into edible products for human consumption.

Fermentation of milk, meat and fish, fruits and vegetables, and cereal grains by micro-organisms creates products which contribute to the flavor, texture and keeping quality of food, suppress the growth of disease and spoilage organisms, and enhance the nutritional quality of the final product. Fermentation is the use of enzymes produced by micro-organisms to change an organic compound into other substances such as carbon dioxide and alcohol. Fermentation technology also has been used for the microbial production of enzymes, amino acids, vitamins, and a host of other components used as food ingredients, nutritive supplements, and food processing aids.

In essence, the food processing industry was practicing biotechnology long before it was recognized as a distinct and revolutionary scientific discipline.

One facet of biotechnology of particular application in the food industry is genetic engineering. This technique is used in the laboratory to alter the genetic material of living cells so that they can produce more or different chemicals or perform new functions. It will have a profound impact on agriculture and traditional food processing because of the tremendous potential for genetic improvement of plants, animals and micro-organisms.

The interface between biotechnology and food processing was explored in October 1985 at an International Symposium, Biotechnology in the Food Processing Industry, cosponsored by the Department of Food Science and Nutrition and the Agricultural Experiment Station at the University of Minnesota, and the Cooperative State Research Service of the U.S. Department of Agriculture (USDA).

Now let us focus on the manipulation of micro-organisms in the production of food additives and processing aids, and their role in the development of value-added technology, improved processing methods, and more efficient use of food processing wastes. Many examples are from the symposium proceedings.

Food Additives and Processing Aids

Some of the products, including enzymes, amino acids, vitamins, organic acids, and certain complex carbohydrates and flavoring agents used in food formulation are currently produced by microbial fermentation. In the future, biotechnology will be used to design micro-organisms capable of producing these high-value additives more efficiently and cost effectively. In addition, advances in large-scale fermentation systems and bioprocess design will optimize recovery and downstream processing of microbial products. All of these will have a profound impact on the food industry.

Some food ingredients are extracted from plant material or synthesized chemically (i.e., gums, flavors, pigments). In the future it will be possible to transfer the genetic ability of the plant to synthesize certain flavors, pigments or complex carbohydrates into food-grade micro-organisms. This transfer will allow commercial production of these high-value food additives via fermentation processes.

Enzymes. The food processing industry is currently the largest consumer of industrial enzymes, making up about 40 percent of a $400 million market. An enzyme is a complex protein produced by living cells that helps a chemical reaction along without itself being changed. Enzymes are added during food processing to control texture or appearance, enhance nutritive value, and generate desirable flavors and aromas.

Future application of biotechnology will involve enzyme engineering changing the primary structure of an enzyme. Such changes may alter target specificity, acidic condition, or thermostability. Enzyme engineering can be used to "tailor-make" enzymes to function best in commercial food processing systems.