Published on 06/26/01

Scientists Singling Out Tastiest Tomatoes

Photo: Scott Bauer, USDA-ARS

Picture-perfect, slicer-type tomatoes from the supermarket may taste great. Or not. Food scientists are trying to make them more predictably tasty.

New tomato varieties are typically bred for disease resistance, high yields and how well they ship. But food scientists are searching for tomatoes that taste good, too.

"We know there's a lot of consumer dissatisfaction when it comes to store-bought tomatoes," said Rob Shewfelt, a food scientist with the University of Georgia College of Agricultural and Environmental Sciences.

"What we want to find out," he said, "is what consumers don't like about the flavor and what can be done about it."

The tomato project research team includes Shewfelt; Jay Scott of the Gulf Coast Research and Education Center in Bradenton, Fla.; Liz Baldwin of the U.S. Department of Agriculture Subtropical Fruit Station in Winter Haven, Fla.; and Harry Klee of the University of Florida.

What do consumers want in a tomato?

"A lot of work has been done on genetic modification of tomato flavor," Shewfelt said. "But no one I know of has defined the quality standards from the consumer's standpoint."

With USDA funding, the team evaluated more than 50 tomato types from Scott's collection. "We wanted to test several selections so we would have a wide range of tomato flavors," Shewfelt said.

The evaluated tomatoes were picked half-ripe and breaker (when the tomato is just showing signs of ripening).

Klee looked at the differences in the genes of the selections. Baldwin tested the tomatoes using a chemical flavor analysis.

UGA-trained and nontrained consumer panelists then tasted the samples, rating their flavor "great," "acceptable" or "not acceptable."

"We found the characteristics for 'great' are different from those of 'acceptable,'" Shewfelt said. "A premium tomato would obviously be one our consumers ranked as 'great.'"

The selections were ripened before the taste tests. Panelists thought some tasted great when picked table-ripe. But they ranked the same tomatoes unacceptable when picked at the breaker stage.

Some varieties rated pretty good whether they were picked ripe or at breaker. And some, Shewfelt said, tasted great when picked red-ripe, "but if you picked them breaker, they tasted just awful."

Until now, breeders picked the best tomatoes

Evaluating flavor has always been a part of tomato variety selection, Shewfelt said. But until now, the breeders did the tasting.

"Breeders taste them when they are ripe, and they choose the varieties based on how well they ship," he said. "But since tomatoes aren't shipped ripe, we're looking for selections that are acceptable when picked breaker (unripe) and allowed to ripen."

The researchers are close to defining what consumers like. They're also identifying the tomatoes consumers rank highest and comparing their flavor characteristics.

"Once we identify the ones with really great flavors, we can work with geneticists to identify the genes that cause these flavors," he said. "Then we can screen selections for these genes and not have to put each through the consumer tests."

Shewfelt's goal is to identify varieties consumers will accept so commercial packers can develop a tomato brand name shoppers will grow to recognize.

"If you knew reliably, eight times out of 10, you're going to be happy when you buy this tomato, you'd probably be willing to spend more money for it," he said. "It's going to take a lot of integration to get to that point. But we're well on the way."

Until the research is completed, shoppers have to keep gambling with tomato taste at the supermarket.

Grape tomatoes best bet for tasty tomatoes

"You can buy grape tomatoes," Shewfelt said. "They have much more flavor than store-bought slicing tomatoes. They just don't work for hamburgers. But they're perfect for salads."

Shewfelt said shoppers have grown to trust grape tomatoes to have good flavor.

"When I buy them, I know I've got a good chance of getting a good-tasting tomato," he said. "But when I buy big, slicer-type tomatoes, I have no clue as to whether it will have any flavor."

Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.