Shortening is what type of fat
Now that trans fats are banned in the United States, however, shortenings have been reformulated to be free of these fats 1. So, should you still avoid shortening? This article takes a look at the research, explaining what shortening is and how it affects your health. Shortening can be made from either animal fat or vegetable oil, but most shortening available today is made from vegetable oils like soybean, cottonseed, or palm oil.
Because these vegetable oils are liquid at room temperature, they must go through a unique manufacturing process called hydrogenation to become solid at room temperature 2. However, the Food and Drug Administration completely banned trans fats in the United States as of January because they can disrupt cell membrane function, leading to an increased risk of heart attack, stroke, and nervous system dysfunction 1 , 3.
Shortening is still made using hydrogenation, but the oils are fully hydrogenated rather than partially hydrogenated, so there are no trans fats present 2. This hydrogenation process fully saturates the vegetable oil molecules with hydrogen ions until they have the characteristic firmness of saturated fats like butter, lard, and coconut oil at room temperature 2.
Shortening is used for specific purposes in cooking and baking. Shortening and other solid fats are preferable to liquid oils in baking applications like cookies, pie crusts, and cakes to create a tender, flaky end product. This gives baked goods like bread a chewy, stretchy texture. But when a fat such as shortening is cut into flour before baking, it coats the gluten strands, preventing them from lengthening and forming a tough matrix. This results in a tender, crumbly, and flaky product 4.
Although butter and lard can accomplish the same result, vegetable shortening is cheaper and more shelf-stable. Until recently, it was also thought to be healthier because it contains less saturated fat than butter and lard.
However, we now know that highly processed shortening offers no health advantages over butter or lard and may in fact be a less nutritious choice 5 , 6. Shortening is used in baking to give pastries a tender texture. Therefore, it is very high in calories and contains neither carbs nor protein.
It also contains very few vitamins and minerals. For example, a tablespoon 12 grams of Crisco All-Vegetable Shortening contains 9 :. When oils are fully hydrogenated, they are completely changed from unsaturated fats to saturated fats , so no trans fats are produced.
Yet full hydrogenation results in a very hard fat, which no longer has a soft, spreadable texture. Therefore, fully hydrogenated oils are commonly blended with liquid oil in a process called interesterification, which results in a spreadable texture 2.
The health effects of interesterified fats are still largely unknown. Unfortunately, though, recent rat studies on the effects of interesterified fats look fairly grim. In one study, researchers found that these fats promoted inflammation, enlargement of the fat cells, and fatty liver disease in rats.
Saturated fat contributes the most to elevating blood cholesterol levels, especially LDL the bad cholesterol. Typically saturated fat is found in animal fats and tropical oils. They tend to be more solid at room temperature.
Unsaturated fats poly and mono have less of an effect on elevating blood cholesterol levels. This, however, does not mean you can guzzle down the olive oil. Fat is still fat and you want a low total fat intake as well. Unsaturated fats are typically from plant sources and tend to be liquid at room temperature. Mono-unsaturated fats may help increase HDL the good cholesterol.
Trans-fatty acids occur during the chemical process called hydrogenation. This is where a mostly unsaturated fat is "hydrogenated" to make it more saturated and thus more solid at room temperature. Margarine and shortening are examples. Trans-fats tend to have more of an effect on elevating blood cholesterol levels, especially LDL, compared to unsaturated fats, but they have less of an effect compared to saturated fat.
Bottom line: eat an overall low fat diet. When you do use fats try to use unsaturated fats, followed by trans-fats and lastly saturated fats.
Shortening is used in most doughs and batters, to give the baked product a crisp and crumbly texture. Rubbing the fat in causes the baked product to have a flaky texture, as the dough is separated into layers. When fat is whisked with sugar, a process called creaming, the texture will be more like a cake, and be soft and springy. The type of fat used will also affect the colour of the product.
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