Fortified food, use of essential fatty acids


The definition of essential fatty acids (EFA) is not clear and univocal: the term “essential” can be interpreted in a narrow way, i.e. what one necessarily needs to take in with the diet, since the body is not able to synthesize it, or in a more extended way, i.e. what is essential for the life of a person, including in this way a much greater amount of fatty acids. In both cases it is still long-chain fatty acids rich of double bonds or unsaturation (hence the abbreviation PUFA: polyunsaturated fatty acids), which makes the structures of these fatty acids more fluid and flexible. This fact is important considering that structures such as cell membranes (including those neuronal) are very rich in fatty acids. Considering the term “essential” to a limited extent, there are only two truly essential fatty acids, i.e. not synthesizable by the human body (and thus also referred to as “vitamin F”): alpha-linolenic acid (one omega 3-ω3) and linoleic acid (one omega 6-ω6). The number after the word omega indicates the amount of carbon atoms from the last carbon atom up to the first double bond. Considering the term “essential” in broad sense, it may include all the polyunsaturated fatty acids of the two series, i.e. ω3 and ω6. Among the “non-essential” ones, the well known are the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA, essential for the composition of phospholipids of synaptic membranes involved in the transmission of nerve impulses), more and more present in supplements and special foods dedicated to pregnancy and early childhood because of the key role they play in proper neuronal and visual development of both fetus and child. ω3 are to be found primarily in fatty fish (salmon, mackerel, anchovies, etc.). The alpha-linolenic acid (essential) is contained in nuts and cold- extracted soybean and corn oils. ω6 are found primarily in cold- extracted vegetable oils but also in some cereals, legumes and vegetables. The population as a whole has often shortage of ω3, rarely ω6. Polyunsaturated fatty acids have many important functions: they are precursors of substances with hormonal effect, called eicosanoids (prostaglandins, thromboxanes, leukotrienes, etc.), they are essential for proper fetal and infant development, energy production, proper functioning of cellular and intracellular membranes (e.g. nucleus and mitochondria), synthesis of hemoglobin, blood clotting, health of skin and joints, sexual function and reproduction, improved glucose tolerance in diabetics, etc. One of the most well-known effects of PUFAs, which is “attractive” for the production of fortified food by the food industry, consists in the power of these substances to reduce blood levels of triglycerides and total cholesterol, and in particularly “harmful” cholesterol, i.e. LDL, resulting in substantial benefits in terms of cardiovascular health. It also seems that PUFAs play an important role in the prevention of neurological diseases such as depression. For all the above mentioned benefic effects, which are now well known to consumers, since for years supported by scientific evidence, food fortification through essential fatty acids is a promising business. This operation, however, is not always easy, since it poses a number of challenges not indifferent to food technology. Let us consider the most critical aspects. Lipid nature: Since they are substances of lipid nature, their intake is simple only in the case of food of the same nature, e.g. fats and creams, or eggs (whose fortification is obtained by adding PUFAs to the diet of laying hens).