Every August, an epic battle takes place in Buñol, Spain. Thousands of participants take to the streets to join the fight. Their weapon of choice? Tomatoes! It’s all part of a festival called La Tomatina that’s been taking place since the 1940s. It’s said to have started as a food fight between friends who turned it into a yearly tradition. The festival is now a major attraction for tourists who want to join in the fun. Participants toss about 120 tons of tomatoes in just one hour, splattering everything and everyone with red pulp.
Tomatoes make for an extra-messy food fight because their thin skin and soft insides allow them to burst easily. Plus, “tomatoes continue ripening after they are picked,” says Ambar Carvallo, a plant geneticist at the University of British Columbia in Canada. Tomatoes contain a carbohydrate, or sugar, called pectin that makes them firm. “Through the ripening process, enzymes [biological substances that speed up chemical reactions] break down pectin to make the tomato squishier,” says Carvallo. The tomatoes grown specifically for La Tomatina are left to overripen. Their mushy texture makes them unsuitable for eating but perfect for smashing.
By the end of the festival, people are covered head to toe in tomato chunks and slip-sliding in a sea of juice. But while today’s tomatoes are fun to toss and squash, ancient tomatoes would not have been suited to the messy brawl, says Carvallo. Tomatoes are descended from a wild fruit originally found in South America: “They were tiny berries,” says Carvallo.