Pandora's Lab: Seven Stories of Science Gone Wrong

by Paul A. Offit

For many reasons, the partially hydrogenated vegetable oils containing trans fats in Crisco were superior to every other cooking oil or shortening ever invented: (1) Trans fats are more stable when exposed to oxygen, so they have much longer shelf lives than animal fats like butter; (2) trans fats burn only at extremely high temperatures, so cooking oils don’t cause much smoke and don’t need to be changed as frequently—a godsend to any employee who works all day over a fryer; (3) trans fats have a neutral flavor, so they don’t interfere with the taste of any food; (4) trans fats look so much like butter that they can easily replace it; and (5) trans fats are extraordinarily cheap. Starting in the 1930s, they were made from oils left over from crushing soybeans used to make animal feed. Finally, because of their variations in texture, structure, lubrication, and aeration, semisolid fats like Crisco allowed bakers to make cakes fluffier, cookies crumblier, crackers crispier, pies flakier, chicken crunchier, and croissants more delicate.