Soft, juicy, delicious tomatoes were a feature of my childhood and are still available from the plants I grow each summer. However, they’ve largely vanished from stores. The ripe fruits don’t hold up well to shipping, so producers have focused on growing variants where mutations have partially blocked the ripening process. These tomatoes stay firm longer, but it comes at the cost of texture and flavor—as well as a decline in their nutritional value.

Now, researchers seem to have identified an enzyme that specifically helps soften the tomato during the ripening process. By knocking its activity down, they’ve interfered with softening while leaving other aspects of the ripening process intact. The result is a ripe fruit that can sit at room temperature for two weeks and still remain firm.

In some ways, the surprise of these results isn’t that they happened; it’s that they took so long. A high-quality tomato genome sequence was first published in 2012, and it allowed researchers to identify more than 50 genes that were likely to encode proteins that could modify the plant cell wall. Four of these genes appeared to be active at high levels in the ripening fruit, and so these genes were targeted through genetic engineering.