Scientists at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) and their partners have found a way to get tomatoes to produce the compounds that make them more flavorful.

According to Gert de Couet, director of the National Science Foundation (NSF) Division of Integrative Organismal Systems, which supported the research, the tomato is one of the most popular foods in the world and researchers believe that their state-of-the-art analysis sets the stage to return it to the taste of decades ago by breeding informed by molecular genetics.

Researchers subjected many tomato varieties to consumer panel evaluations. Step one for UF/IFAS horticultural scientist Harry Klee and his colleagues involved finding out which of the hundreds of chemicals in a tomato contribute the most to taste.

Next, Klee says, they asked: “What’s wrong with modern tomatoes?” As it turned out, modern tomatoes lack sufficient sugars and volatile chemicals critical to better flavor. Those traits have been lost over the past 50 years, says Klee.

The researchers began looking at tomato alleles (one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome). Alleles determine specific traits in organisms, whether tomatoes or people. Klee likened this to how different versions of genes in humans influence traits such as height, weight and hair color.

Researchers wanted to identify why modern tomato varieties are deficient in flavor chemicals. They determined that it’s because they have lost the more desirable alleles of a number of genes.

The scientists then zeroed in on the locations of those alleles in the tomato genome. Using a technique called a genome-wide association study, they mapped genes that control synthesis of all the “tasty” chemicals. Informed by genetic analysis, they replaced undesirable alleles in modern tomato varieties with desirable alleles.

Researchers identified the factors that have been lost and showed how to move them back into modern types of tomatoes.

Breeding a more flavorful tomato could benefit consumers as well as the tomato industry. According to the Department of Agriculture, the U.S. is second to China in worldwide tomato production.