Bob the Tomato

As we watched "The Angry Eyebrows," a Larry-Boy cartoon adventure, a scene is shown where Junior the Asparagus, Bob the Tomato and Vicki are in a food-fight. Junior and Vicki squirt each other and Bob with mustard, while Bob squirts his opponents with ketchup. This prompted me to wonder where ketchup comes from in Bumblyberg. Is Bob a cannibal? Is it his "blood?" Inquiring minds want to know.