Fatty acid profiles of 80 vegetable oils with regard to their nutritional potentialThe current concern for fat intake in western countries has raised the question of the individual fatty acid (FA) impact on health. This important issue has strengthened the awareness of nutritionists and food manufacturers for the control of the FA profile of food products. The aim of this review is to provide a classification of the FA profiles of 80 vegetable oil sources, according to their nutritional potential. The first part of the review focuses on lipoprotein metabolism, and on the impact of each dietary FA on blood lipid composition (LDL-cholesterol, HDL-cholesterol and circulating triacylglycerols). In the second part of the review, the oil sources are clustered by similar FA profiles, and the classification is discussed with regard to the individual FA action on blood lipid composition. Apart from the major vegetable seeds, the clustering highlighted some interesting nutritional oil sources containing mainly a-linolenic acid (camelina, linseed, perilla and stock oils), or interesting amounts of the two essential FA (purslane, chia, raspberry seed, sea buckthorn seed and salicorn oils). Furthermore, this classification provides a useful tool for the formulation of the FA profile of food products. A fatty acid is a hydrocarbon chain, saturated or not, with a methyl group at one end (n), and a carboxylic function at the other (D). An SFA, as its name suggests, possesses an alkane-like structure with a fully saturated hydrocarbon chain, while a MUFA has one double bond, and a PUFA several ones, with these double bonds being naturally in cis configuration [2].
KeywordsVegetable oils are mainly triacylglycerols, made by esterification of three FA on the glycerol skeleton [3]. The three positions are not equivalent when it comes to bioavailability, and a fortiori to health. Indeed, the sn-2 position is conserved during the whole digestive process, which explains why in natural fats and oils the most physiologically important FA are esterified on the sn-2 position [4-6].In vegetable sources, unsaturated FA are mainly esterified on this important sn-2 position [7].Among PUFA, the most important families are the wellknown n-3 and n-6 fatty acids [8]. These two families are similar as they both comprise a precursor, namely ALA for the n-3 and linoleic acid (LA) for the n-6 family ( Fig. 1), and terminal products obtained by a succession of elongations and desaturations during the metabolism, the two groups of FA sharing the same long-chain converting enzymes [2]. These compounds are said to be essential because the human body is unable to synthesize them, although it can metabolize them to longer-chain derivatives. So the diet must cover the organism need for theseThus, a competition exists between n-3 and n-6 FA, with an excess of one group causing a significant decrease in the conversion yield of the other (Fig. 2) (LA, bottom), showing the double bonds in the hydrocarbon chain. The numbers represent the carbon atoms bearing a ...
