By Harold McGee
“Cactus pear” is the modern marketing term for “prickly pear” (Spanish tuna), the fruit of the American cactus Opuntia ficus-indica. The species name comes from the early European idea that the dried fruit was an “Indian fig.” The cactus arrived in the Old World in the 16th century and spread like a weed in the southern Mediterranean and Middle East. While both stem pads and fruits are eaten in the Americas, Europeans concentrated on the fruits, which ripen in the summer and fall and have a thick skin, green to red or purple, and many hard seeds embedded in a reddish, sometimes magenta flesh. The main pigment is not an anthocyanin but a beet-like betain. The aroma is mild, reminiscent of melons thanks to similar alcohols and aldehydes. Like the pineapple and kiwi, cactus pears contain a protein-digesting enzyme that can affect gelatin gels unless it’s inactivated by cooking. The pulp is removed and generally eaten fresh as juice or in salsas, or boiled down to a syrup or further to a pasty consistency. The paste is made into candies and cakes with flour and nuts.