July 26, 2021

Cold pressed oils – Anna Lewandowska

Recently, organic food, produced in a simple, safe and the least harmful way, is gaining more and more popularity. More and more of you are more aware and realize that how important part of the diet are natural products and unprocessed food. In addition, you pay more attention not only to the composition of products, but also to their origin, method of production and environmental impact. I must admit that I am very happy about it 🙂

Cold-pressed oils are one of the most popular types of natural products. Probably many of you have come across terms such as “cold-pressed oil”, “virgin” or “unrefined” – these are just some of the slogans that manufacturers use to encourage consumers to buy oil. Are cold-pressed oils actually healthier and more valuable for our body, or is it just a simple marketing gimmick? I will try to answer these and other questions in today’s post.

Extracted cold-pressed oils

Cold-pressed oils are obtained from:

  • seeds (e.g. rape, flax, sunflower, borage)
  • seeds (e.g. pumpkin, grapes, raspberries)
  • fruit (e.g. olives)
  • nuts (e.g. walnuts, hazelnuts or argan trees)
  • plant sprouts (e.g. wheat germ)

The taste, smell, and nutrient content therefore depend on the individual raw materials used in production, as well as on their storage conditions and production methods.

How is Cold Pressed Oil Made?

Cold pressing of the oil using mechanical methods is a process during which the pressing temperature does not exceed 40 ° C, which guarantees the preservation of valuable health and taste properties contained in the grains. Cold pressing of oil is the oldest natural method of its extraction, classified as ecological, as it does not use any solvents.

For comparison, classic oils are pressed with the participation of even 160ºC, and additionally refined (purified) at a temperature of up to 300ºC. As a result, the seeds are deprived of many valuable nutrients. Moreover, refining leads to a product that is neutral in taste.

Cold-pressed oils as functional food

An increasingly common choice of consumers is functional food, i.e. food with health-promoting properties. Such food, in addition to its nutritional function, improves health and well-being and / or reduces the risk of diseases. The presence of various bioactive substances in cold-pressed oils makes them functional food. Cold-pressed oils are a rich source of polyunsaturated fatty acids and sterols, which have a bioactive effect, and antioxidants such as: tocopherols and polyphenolic compounds. The substances contained in oils can take part in the prevention or counteracting of many civilization diseases, such as cardiovascular diseases, cancer or obesity, and they can also delay the aging process.

Health-promoting properties of cold-pressed oils

Cold-pressed oils are a very valuable source of essential, unsaturated fatty acids (EFAs). The human body is not able to synthesize them on its own, which means that it is necessary to constantly supply them with food. Omega-3 and omega-6 polyunsaturated fatty acids have a positive effect on the lipid profile, reducing the level of LDL cholesterol, i.e. bad cholesterol, thus preventing the development of atherosclerosis. They regulate the work of the cardiovascular system and help maintain normal blood pressure. In addition, they counteract the degeneration of neurons, i.e. protect against damage to the cells of the nervous system, and thus contribute to lowering the risk of developing Alzheimer’s disease. They also have anti-inflammatory and anti-allergic properties.

Omega-3 fatty acids are particularly important during the development of the fetus and in early childhood, because they affect, inter alia, for the proper development of the brain and the shaping of the organ of vision.

Other substances found in cold-pressed oils are antioxidants, such as tocopherols and polyphenolic compounds, which exhibit antioxidant properties. They play an important role in reducing oxidative stress, i.e. a condition caused by the accumulation of free radicals that damage the cells and tissues of the body and, consequently, contribute to the development of many chronic diseases, including diabetes, atherosclerosis, heart disease and even cancer.

Plant sterols, or phytosterols, are another group of compounds present in oils that have a beneficial effect on human health. Phytosterols have the ability to lower LDL cholesterol and total cholesterol in the blood by limiting the absorption of cholesterol from the intestines. Thus, they constitute a natural protection against cardiovascular diseases. Scientific studies show that the consumption of 1.5-2 g of plant sterols or stanols lowers the plasma concentration of LDL cholesterol by 9-14%. Additionally, plant sterols are believed to exhibit anti-inflammatory, antibacterial, anti-ulcer and even anti-cancer properties.

Cold pressed or refined oil?

Each oil differs from each other not only in terms of the content of bioactive compounds, but also in taste, smell and durability. It is influenced by many factors, such as the type of raw materials used for production, storage conditions and production methods.

One of the main advantages of using cold-pressed oils is the high content of monounsaturated and polyunsaturated fatty acids, as well as the presence of antioxidants such as tocopherols and polyphenolic compounds, which show high antioxidant activity. Cold pressed oils are characterized by a higher content of linoleic and linolenic acids, which are essential fatty acids (EFAs). This means that these oils have a greater nutritional value, making their positive health effects greater. In addition, cold-pressed oils have a characteristic taste and smell, appropriate to the raw material from which they were produced.

However, in the case of classic oils, as a result of pressing at a very high temperature and during the refining process, the content of many valuable ingredients, such as e.g. tocopherols, sterols or polyphenolic compounds, is reduced. In addition, refining leads to a product that is neutral in taste and smell.

Application in the kitchen

The Food and Nutrition Institute recommends increasing the supply of vegetable fats, especially those consumed cold, while informing about the reduction of the supply of animal fats. In such a situation, how can you use the oils raw? There are many possibilities, for example: for sprinkling salads and salads, as an addition to dips or dressings, as an ingredient for pesto or sandwich spreads, which are a great alternative to butter or simply to sprinkle bread.

What about frying? If you decide to use this culinary processing technique, the use of refined oil will be a much better choice. Why? Because cold-pressed oils have a lower smoke point, the temperature at which fat breaks down and loses its nutritional value. However, in the case of classic oils, the refining process affects, among others, on the composition of fatty acids, and thus on their durability, thanks to which refined oils are more stable during frying. The lower the smoke point, the less frying the fat is. It is recommended to heat treat fats that have a smoke point above 200 ° C.

For comparison, the smoke point of unrefined rapeseed oil is 130 ° C, and of refined oil is 240 ° C. It is similar in the case of sunflower oil, the temperatures of which are respectively: 107 ° C and 220 ° C. By contrast, the cold-pressed olive oil has a smoke point of 191 ° C and linseed oil only 107 ° C.

Storage

Cold-pressed oils, due to the fact that they are not subjected to high temperatures, are less chemically stable, which means that they are less stable during storage and can oxidize quickly. Therefore They should be stored preferably in glass, dark and tightly closed bottles that limit the access of light and in a cool place, such as a refrigerator.

Summary

Growing consumer awareness is conducive to making better nutritional choices, including choosing good-quality vegetable fats. Although cold-pressed oils account for a small share of the edible oils market, they are gaining more and more followers preferring natural and unprocessed food. Cold-pressed oils show a higher nutritional value compared to refined oils, and are also characterized by a better taste and smell. Therefore, it is worth considering increasing their supply in the daily diet, because thanks to, inter alia, the content of bioactive compounds may reduce the risk of developing many civilization diseases.

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