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Food Lipids: Chemistry, Nutrition, and Biotechnology

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Table 1 Major Fatty Acids in Some Edible Fats <strong>and</strong> Oils<br />

Formula Fatty acid Source<br />

Saturated fatty acids<br />

MCFA Medium chain fatty acids Dairy fat, coconut oil, palm<br />

kernel oil<br />

C12:0 Lauric acid Dairy fat, coconut oil, palm<br />

kernel oil<br />

C14:0 Myristic acid Dairy fat, coconut oil, palm<br />

kernel oil<br />

C16:0 Palmitic acid Palm oil, meat<br />

C18:0 Stearic acid Meat, cocoa butter<br />

Monounsaturated fatty acids<br />

C18:1,n-9<br />

Polyunsaturated fatty acids<br />

Oleic acid Olive oil, rapeseed oil, high<br />

oleic acid sunflower oil<br />

C18:2,n-6 Linoleic acid Sunflower oil, corn oil, soy<br />

bean oil, corn oil<br />

C18:3,n-3 �-Linolenic acid Rapeseed oil, soy bean oil<br />

C20:5,n-3 a<br />

Timnodonic acid Fatty fish, fish oil capsules<br />

Cervonic acid Fatty fish, fish oil capsules<br />

C22:5,n-3 a<br />

a<br />

The trivial name for timnodonic acid is eicosapentaenoic acid (EPA) <strong>and</strong> for cervonic acid docosahexaenoic<br />

acid (DHA).<br />

<strong>and</strong> polyunsaturated fatty acids. About 30–40% of total energy intake is provided<br />

by fat. For a person consuming 10 MJ (2400 kcal) per day, this corresponds to a fat<br />

intake of 80–107 g.<br />

III. LIPOPROTEINS<br />

The solubility of cholesterol in water is very low, approximately 5.2 � 10 �3<br />

mmol/L. The actual cholesterol concentration in the watery plasma of healthy subjects,<br />

however, is about 3.9–5.2 mmol/L, <strong>and</strong> increases to more than 10 mmol/L in<br />

hypercholesterolemic people. This high degree of solubilization is achieved by the<br />

formation of lipoproteins.<br />

Lipoproteins are globular, high molecular weight particles that are complex<br />

aggregates of lipid <strong>and</strong> protein molecules. A lipoprotein consists of a hydrophobic<br />

core, which mainly contains triacylglycerols <strong>and</strong> cholesterylesters, <strong>and</strong> a polar, hydrophilic<br />

coat composed of phospholipids, unesterified cholesterol, <strong>and</strong> specific apolipoproteins.<br />

In this way, the hydrophobic core is protected from the watery surrounding<br />

<strong>and</strong> transport of large amounts of cholesterol <strong>and</strong> triacylglycerols through<br />

the blood vessels is possible.<br />

Lipoproteins are a heterogeneous group, which can be divided into five major<br />

classes: chylomicrons, very low density lipoproteins (VLDLs), intermediate density<br />

lipoproteins (IDLs), low density lipoproteins (LDLs), <strong>and</strong> high density lipoproteins<br />

Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.

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