The "Indigo Rose" tomato steps out this year as the first "really" purple variety to came from a program at Oregon State University that is seeking to breed tomatoes with high levels of antioxidants. The new variety is a novelty type intended for home gardens and the fresh market, and it is now available in seed catalogs, said Jim Myers, a professor in the OSU horticulture department.
"It is the first improved tomato variety in the world that has anthocyanins in its fruit," he said.
The new tomato is released as an open pollinated variety, and as such, seed saved from self-pollinated plants will grow true and not produce hybrids. "It's also important to know that genetic engineering techniques are never used to develop these lines," Myers said. "These tomatoes are not GMO."
Does the new variety taste good?
"People are passionate about their tomatoes," Myers said. "The purple color draws their interest and because it's extraordinary, people tend to expect impressive flavor as well. It does have a good balance of sugars and acids and tastes just like a tomato. Anthocyanins are essentially tasteless."
Myers cautions not to pick the tomato too soon. Indigo Rose must be allowed to ripen fully for complete development of sugars and acids. It's easy to harvest too early because the usual visual clues won't be there.
The tomatoes will be purple where exposed to light, Myers said, and they tend to have a purple crown. They are ripe when their color changes from a shiny blue-purple to a dull purple-brown. The fruit also softens similarly to regular tomatoes, and the bottom of the tomatoes will turn from green to red when ripe.
Anthocyanin produces in the fruit only where exposed to sunlight. If shaded by a leaf or on the base, the purple pigment does not develop. "However, if you pick an Indigo Rose and expose the non-purple area to sunlight, it will turn purple in about a week," Myers said.
