Hydrogenated fats are lipids which - to achieve chemical-physical characteristics useful for the needs of the food industry - undergo a defined manipulation hydrogenation.
Hydrogenation: what is it for?
Hydrogenation is a chemical process useful for the saturation (usually partial) of naturally polyunsaturated fatty acids; polyunsaturated fatty acids also have double bonds between the carbon atoms of the chain, consequently binding fewer hydrogen ions than a saturated fatty acid.
Hydrogenation consists in simplifying the double bonds to single bonds, to increase the quantity of hydrogen ions and acquire greater saturation. As this last chemical characteristic increases, the solidity of the product also increases; consequently, thanks to the hydrogenation process, it is possible to transform an oil (liquid at room temperature) into a solid or semi-solid fat.
They can be hydrogenated:
- Fats deriving from a single source
- Fat blends
- Mixtures of non-hydrogenated fats and oils
Hydrogenated fats find great application in the industrial preparation of baked goods and in the composition of margarines sold at retail.
In the "food industry, hydrogenated fats are synthesized on the basis of the plastic need for processing and the friable potential, needs to which in the past saturated animal fats (butter, lard, tallow and lard) met. To date, hydrogenated fats have displaced almost totally saturated animal lipids for:
- lower cost
- greater specificity of use
- greater thermal stability
- greater organoleptic stability
- greater shelf life.
Hydrogenated fats and health
Hydrogenated fats are not essential nutritional components or useful for the functioning of the organism; metabolically, they behave exactly like animal saturated fatty acids, playing a hyper-cholesterol-lowering role in the low-density lipoproteins (LDL) and hypo-cholesterol-lowering in the body. high density lipoprotein (HDL). However, if it is true that hydrogenated fats do not contain cholesterol most of the time, they are distinguished by another harmful potential: the presence of fatty acids trans.
Often, during the hydrogenation process, the saturation fails but the structure of the fatty acid still undergoes a significant alteration; it is a molecular geometric conversion from Are you there to trans which modifies its functions and metabolism within the human body. It is true that hydrogenated fats are not the only source of trans acids, which can also be found among the lipids of sheep, ox and in dairy products; the most naturally occurring trans molecule is the elaidic acid, which corresponds to the cis-oleic. Compared to saturated or hydrogenated fatty acids in cis form, trans fatty acids favor even more the "raising of LDL while reducing HDL in parallel; a diet rich in trans fatty acids can represent a risk factor for cholesterol dyslipidemia and cardio-vascular complications. Therefore, the use of margarines or hydrogenated fats in place of animal lipids is not to be considered a completely correct dietary choice.
Bibliography:
- Manual of oils and fats - P. Capella, E. Fedeli, G. Bonaga, G. Lerker - New techniques - 12.3
- Clinical Nutrition Manual - R. Mattei - Maedi-Care - pages 37-38
