When a cis double bond is introduced into the acyl chain this creates a kink in the structure. Because of this, the acyl chains cannot align completely along their length - they don't pack together as well.
Because of this, the sum of the energy associated with intermolecular Van der Waals interactions is reduced. Again this is seen clearly in the melting temperatures of fatty acids:. As you can see from these numbers, the effect of introducing a double bond is large compared to the chain length effect.
A typical fat or oil will, of course, be a mixture of different triacylglycerols, but the underlying principle is the same. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Saturated vs unsaturated fats - Structure in relation to room temperature state? An unsaturated fat can be made in to a saturated fat via hydrogenation reactions.
Unsaturated fatty acids may be converted to saturated fatty acids by the relatively simple hydrogenation reaction. Recall that the addition of hydrogen to an alkene unsaturated results in an alkane saturated. A simple hydrogenation reaction is:. Vegetable oils are commonly referred to as "polyunsaturated".
This simply means that there are several double bonds present. Vegetable oils may be converted from liquids to solids by the hydrogenation reaction. Margarines and shortenings are "hardened" in this way to make them solid or semi-solids. Vegetable oils which have been partially hydrogenated, are now partially saturated so the melting point increases to the point where a solid is present at room temperature.
Foods made with butter, margarine, or shortening cakes, cookies, and other desserts have a lot of saturated fat. Saturated fat can raise your cholesterol. This is a fat that has been changed by a process called hydrogenation. This process increases the shelf life of fat and makes the fat harder at room temperature.
Harder fat makes crispier crackers and flakier pie crusts. Trans fat can raise your cholesterol, so eat as little trans fat as possible. You'll find it in:. Unsaturated fat is liquid at room temperature. It is mostly in oils from plants. If you eat unsaturated fat instead of saturated fat, it may help improve your cholesterol levels.
Try to eat mostly unsaturated fats. Monounsaturated fat and polyunsaturated fat are types of unsaturated fat. Review the nutrition facts label on food packaging to learn the total fat, saturated fat, and trans fat. Food labels are not required to list monounsaturated and polyunsaturated fat. Author: Healthwise Staff. However, there have been multiple studies that refute the detrimental effects of saturated fat. Although the amount of LDL in your body appears to be increased by consuming saturated fats, studies have shown that the type of LDL that is increased is actually the large, buoyant LDL.
Larger LDL particles do not appear to increase your risk of heart disease. In contrast, small, dense LDL —the type that has been shown to promote the formation of atherosclerosis —doesn't appear to be affected.
In a few cases, the risk was even reduced with saturated fat consumption. Some studies also suggest that the type of saturated fat-containing foods can make a difference in your heart health. One large study suggested that consuming dairy products may actually lower the risk of cardiovascular disease. At the same time, including processed meats in your diet could increase your risk of cardiovascular disease.
Based on available evidence, experts disagree on how important it is to limit saturated fats in your diet. The AHA recommends limiting dietary saturated fats. Fats from dairy products are considered a safe choice. And all experts agree that processed meats should be avoided. Unsaturated fats are typically liquid at room temperature. They differ from saturated fats in that their chemical structure contains one or more double bonds. They can be further categorized as:.
The AHA recommends that most of your daily fat intake should come from monounsaturated and polyunsaturated fats. Foods containing unsaturated fats include:. Cholesterol and fats are both lipids and they are found in the food you eat and circulating in your bloodstream. Cholesterol has a more complex chemical structure when compared to fats.
In the body, cholesterol is bound to protein as low-density lipoprotein LDL which is considered to increase heart health risks, and high-density lipoprotein HDL , which is called good cholesterol because it is considered healthy.
While saturated fat, the kind found in beef, butter, and margarine, can raise your LDL levels, the kind of LDL large LDL particles may not increase your cardiovascular risk. Your best bet might be to moderate the saturated fats in your diet and to avoid the specific foods known to increase risk, particularly processed meats. If you are watching your cholesterol and triglyceride levels, try to include a variety of healthy foods like lean meats, vegetables, fruits, legumes, and whole grains.
More research is needed to understand the influence of unsaturated and saturated fats on cardiovascular disease. Although there has been research suggesting that saturated fats are not as bad for heart health as once thought, the current recommendations remain in place.
Both unsaturated fat and saturated fat add calories to your meal and weight to your waistline if you consume too much of either one, so it is best to eat them in moderation. Additionally, the type of fat-containing foods you consume can make a difference in your lipid levels. A handful of walnuts or a lean piece of beef is a better choice for your meals in comparison to a bag of chips or sausage links.
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