What's this
What is various seed oil?
By various seed oil - various seed oil - is meant a fatty alimentary mixture of vegetable origin obtained from the processing of the endosperm, not from the pericarp, of the fruits of some plants.
This last clarification is fundamental. In the oil of various seeds may be present, for example, olive oil oil - more often from pomace - and palm kernel-palm kernel oil. The pericarp - pulp - of the same fruits is not used instead, from which olive oil is obtained in the first case and palm oil in the second.
Features
Characteristics of various seed oils
The oil of various seeds is generally quite cheap. This feature is mainly due to two factors.
- Low cost raw materials: among the most used seeds for this kind of oil we remind: sunflower, rape, corn, soy, peanuts and olive.
- Very profitable and efficient extraction method: combination of mechanical (squeezing) and chemical (solution in inert solvents and distillation) systems.
Obviously there is no lack of further refining processes, which depend on both the specific ingredient and the type of oil in question.
Rarely seed oils are produced already from the first stage of processing, ie from mechanical-chemical extraction. Companies prefer to buy intermediate products that are already partially processed. They can follow further arrangements, such as the bleaching, deodorization or fractionation of fatty acids - commonly called "refining" - the addition of antioxidants - for example vitamin E - and the union in mixtures obtained from specific recipes.
For this reason, "various seed oil" may mean everything and nothing. There are various seed oils with chemical - therefore nutritional, with their metabolic and physical impact - point of smoke, resistance to oxidation or peroxidation, general shelf life etc. - totally different from each other.
The oils of various seeds are usually all of fluid consistency at room temperature, which suggests a low percentage of saturated fatty acids. Without consulting the product label, it is impossible to identify the individual percentages and types of unsaturated (monounsaturated and polyunsaturated).
A seed oil rich in essential omega 3 and omega 6 polyunsaturated fatty acids, respectively alpha linolenic acid (ALA) and linoleic acid (LA), on the one hand ensures a good metabolic impact - taking for granted the right ratio between omega 3 and omega 6 - but on the other hand it affects the use in cooking and storage - with sensitivity to sunlight, high temperature, oxygen, free radicals etc. A good compromise is instead that of oils rich in oleic acid, a monounsaturated from the omega 9 family. This fatty acid, while having a positive action on metabolism, is also very resistant to cooking and is not easily damaged during storage.
The presence of antioxidants, liposoluble and tendentially vitaminic - such as tocopherols or vit E - is almost always the result of the addition of food additives. The processing techniques of various seed oils are based on mechanisms that damage or destroy the most delicate components of the raw materials, such as: thermolabile vitamins, phytosterols and polyphenols, chlorophylls, etc.
Nutritional Properties
Nutritional properties of various seed oils
Various seed oil is a product that belongs to the V fundamental group of foods - fats and seasoning oils. It should have the role of providing the right amounts of essential fats, more generally of beneficial lipids, fat-soluble vitamins (especially vit E and vit A) and other antioxidants such as phytosterols.
As we have said, the nutritional properties of various seed oil depend above all on the chemical composition of the product.
Not being able to use a single model to analyze, below we will propose an example table on the characteristics of the main fatty acids that can compose the oil of various seeds.
| Fatty acid name | Property |
| Alpha linolenic acid â? “ALA | Polyunsaturated of the omega 3 group. It is essential for humans but not bioavailable; it must be converted â? "with the same enzymes involved in the omega 6 â?" cycle in the active metabolites eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). It has a liquid consistency and is sensitive to high temperatures, oxidation â? "Oxygen and free radicals â?" And to light. It requires an accurate conservation, in the dark, without air and in the cool, and the protection of antioxidants such as vitamin E. In the biologically active forms, the omega 3 constitute the cellular membranes, allow the nervous and ocular development, preserve the cognitive function, increase anti-inflammatory blood factors and plasma thinning. They are also responsible for the prevention and improvement of certain metabolic pathologies such as arterial hypertension and hypertriglyceridemia; apparently they can moderate the damage of type 2 diabetes mellitus. In the past it was believed that they could reduce bad cholesterol or increase good cholesterol; the results are mixed. |
| Linoleic acid â? “LA | Polyunsaturated of the omega 6 group. It is essential for humans. It is converted â? "With the same enzymes involved in the omega 3 â?" Cycle in other metabolites such as arachidonic acid. It has a liquid consistency and is sensitive to high temperatures, oxidation â? "Oxygen and free radicals â?" And to light. It requires an accurate conservation, in the dark, without air and in the cool, and the protection of antioxidants such as vitamin E. It carries out many very important functions, including the synthesis of eicosanoids, both anti-inflammatory, such as omega 3, and pro-inflammatory. They are also responsible for the prevention and improvement of certain metabolic pathologies; it seems that, in contrast to omega 3, they have a significant positive influence on cholesterolemia. |
| Oleic acid â? “OA | Monounsaturated from the omega 9 group. It is not essential for humans. It has a liquid consistency and is not very sensitive to high temperatures, to oxidation â? "Oxygen and free radicals â?" And to light. For this reason, it is the most abundant in oils aimed at preserving in oil; It is also excellent for cooking. Requires not too careful conservation. It has a globally positive effect on metabolism â? “Especially on lipemia. |
| Palmitic acid â? "PA | Saturated not essential for man. It has a basically solid consistency and is resistant to high temperatures, oxidation â? "Oxygen and free radicals â?" And to light. It features some vegetable oils, such as palm and plamisto, excellent for frying. It is also abundant in animal fats. From a metabolic point of view it is considered harmful, if in excess. It tends to increase cholesterolemia and is indirectly associated with arterial hypertension. It can increase cardiovascular risk factors. |
| Stearic acid - SA | Saturated not essential for man. It has a basically solid consistency and is resistant to high temperatures, oxidation â? "Oxygen and free radicals â?" And to light. Like the previous one, it features some vegetable oils, such as palm and plamisto, excellent for frying. It is also abundant in animal fats. From a metabolic point of view it does NOT seem to have such a negative impact as that of palmitic acid, but not even as beneficial as poly- and mono-unsaturated ones. |
Diet
Varied seed oil in the diet
Various seed oils should not be the only dressing fat present in the diet. This is because they tend to be of poor quality and almost none of them perform the specific function of this group of foods, or to increase the intake of useful lipid molecules such as: beneficial fatty acids (omega 3, omega 6 and omega 9), vitamin E, phytosterols, lecithins, etc.
Furthermore, we specify once again that the usefulness of these foods depends above all on their chemical and physical properties. In practice, their predisposition for seasoning raw or for frying can only be established, in this specific case, by consulting the nutritional label.
In general, we can say that an oil of various seeds rich in unsaturated polyunsaturated molecules lends itself to seasoning raw. If prevalently monounsaturated, it can also be used for cooking. Although rarely, if it contains many saturated fats, it is more suitable for frying than anything else - but it has negative nutritional characteristics and moderate and sporadic use is recommended.
