Genetically altered tomatoes have plenty of people seeing red

March 24, 1993|By Karol V. Menzie | Karol V. Menzie,Staff Writer

If you regularly include tomatoes on your grocery shoppin list, take warning now: Selecting tomatoes is about to become a more difficult matter.

Or not.

But in coming months -- late summer or early fall, depending on the harvest -- when Calgene Fresh of Evanston, Ill., introduces its new MacGREGOR-brand tomatoes, shoppers across the country are going to have to make some decisions.

How volatile that process is going to be was foreshadowed in a presentation Sunday at the annual meeting of the American Institute of Wine and Food, in Washington.

The San Francisco-based group, founded to promote interest in and knowledge of food and wine, spent most of its four-day "Conference on Gastronomy" on topics relating to food as culture, in conjunction with the Smithsonian Institution's Columbus commemoration exhibit "Seeds of Change." They also ate foods prepared by California and Washington-area chefs, sampled wine, and rubbed elbows with such luminaries as AIWF founder JuliaChild, anthropologist Lionel Tiger, plus winemakers, restaurateurs, cookbook authors and food journalists from across the country.

Sunday's final session brought together scientists, chefs, academics, government and consumer advocacy representatives and journalists for "The Great Biotech Debate." At issue: Whether scientists should apply the tools of biotechnology to altering the food supply.

The MacGREGOR tomato will be the first genetically modified product of its kind to hit grocery shelves, and it has become a lightning rod for concerned parties on both sides of the debate. The tomatoes are grown from a new variety of seed, called FLAVR SAVR. Unlike all previous new varieties, this one is not the product of traditional cross-breeding techniques. Instead, it is the product of genetic engineering.

Steve Benoit, vice president of marketing at Calgene Fresh, said that in the past, commercial tomato growers have had to worry about three major factors: yield, uniformity and durability. That's what it took to get tomatoes to market. Taste was hardly considered. With the FLAVR SAVR, Mr. Benoit said, "We're able to leave the fruit on the vine three to five times longer. That's when the acids and sugars that create flavor are developed."

In creating the tomato, genetic engineers extracted a gene -- a piece of the blueprint that determines hereditary characteristics in all living organisms -- from an ordinary tomato, reversed it, and reinserted it into the genetic message string that determines the nature of the plant. The gene controls an enzyme called polygalacturonase (polly-galac-TUR-oh-nase) that causes the tomato fruit to soften. In the wild, tomatoes must soften and decay in order to release their seeds -- and start the growing process over.

But in the tomato trade, this message to soften comes far too early. Tomatoes left on the vine until they are ripe enough to eat would quickly move into the rotting stage. And since "fresh" tomatoes may be two or three weeks in transit between grower and grocery produce counter, they are picked when still hard and green, with the expectation that when they get to consumers, they will have begun to ripen. In practice, tomatoes treated in this fashion do not fare well, and come to consumers pink and mushy.

But, in the FLAVR SAVR tomato, 99 percent of the "soften" message is blocked. That prolongs the softening process for about a week. So FLAVR SAVR tomatoes can be left on the vine a few days longer, until they are a few days riper, and, it is hoped, will arrive at the grocery with more "vine-ripe" flavor and texture.

Dr. Roger Beachy, a plant biologist with the Scripps Research Institute in La Jolla, Calif., noted that certain genetic engineering techniques, such as cell fusion and embryo rescue, have long played an important role in the development of new varieties of plants. New varieties are needed, he said, because "agriculture has become completely chemically dependant" -- that is, today's commercial varieties require chemical fertilizers for growth and pesticides to protect them from pests and disease. His goal, Dr. Beachy said, is the development of plants that need "less chemical intervention to prosper."

But Rebecca Goldberg, a biologist with the watchdog Environmental Defense Fund, said, "Genetic engineering allows producers to do anything to a plant. It's blurring the distinction between processed and unprocessed foods." All genes carry codes for proteins, she said, and all known true allergenic substances are proteins. (Food allergies are a reaction of the body's immune system to a substance in food; some people suffer from food intolerances, such as lactose intolerance, that don't involve the immune system and are not allergies.) She suggested more work needs to be done on issues of protein safety, allergenicity, and potential unintended side effects before any genetically engineered products enter the market.

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