Shortening

Shortening is any fat that is a solid at room temperature and used to make crumbly pastry and other food products. The idea of shortening dates back to at least the 18th century, well before the invention of modern, shelf-stable vegetable shortening. In the earlier centuries, lard was the primary ingredient used to shorten dough. The reason it is called shortening is that it makes the resulting food crumbly, or to behave as if it had short fibers. Solid fat prevents cross-linkage between gluten molecules. This cross-linking would give dough elasticity, so it could be stretched into longer pieces. In pastries such as cake, which should not be elastic, shortening is used to produce the desired texture. Originally shortening was synonymous with lard, but with the invention of margarine from beef tallow by French chemist Hippolyte Mège-Mouriès in 1869, margarine also came to be included in the term. Since the invention of hydrogenated vegetable oil in the early 20th century, "shortening" has come almost exclusively to mean hydrogenated vegetable oil. Modern margarine is made mainly of refined seed oil and water, and may also contain milk. Vegetable shortening shares many properties with lard: both are semi-solid fats with a higher smoke point than butter and margarine. They contain less water and are thus less prone to splattering, making them safer for frying. Lard and shortening have a higher fat content compared to about 80% for butter and margarine. Cake margarines and shortenings tend to contain a few percent of monoglycerides whereas other margarines typically have less. Such "high ratio shortenings" blend better with hydrophilic ingredients such as starches and sugar. Hydrogenation of organic substances was first developed by the French chemist Paul Sabatier in 1897, and in 1901 the German chemist Wilhelm Normann developed the hydrogenation of fats, which he patented in 1902. In 1907, a German chemist, Edwin Cuno Kayser, moved to Cincinnati, Ohio, the home town of soap manufacturer Procter & Gamble.