They called it Formula 47 in the US, after the total cost in cents of a burger, fries and milk shake in 1960. Formula 47 was a blend of rendered beef fat and vegetable oil, which, when used to fry shoestring slices of Russet Burbank potatoes
University.That doesn't mean you should kick traditionally healthy oils, such as canola oil and olive oil, out of your kitchen. You just have to bear in mind that butter and other nonhydrogenated natural fats are not as bad as nutritionists once thought them
