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Cold-pressed oil – most of us have probably heard this term.  Have you ever wondered, however, what it actually means in practice and how this widely praised cold-pressed oil differs from oil pressed at high temperature?

It is high time to check what really lies behind this advertising slogan.

To do so, however, it is worth briefly tracing the entire oil production process.

How is oil made?

Oil production, in this case vegetable oil, begins with the cultivation of plants suitable for this purpose.

In our climate zone, these are primarily rapeseed, sunflower, flax, poppy, and the somewhat less popular evening primrose.

These plants produce fats because they are one of the main components that provide them with energy and support various life processes. Fats are found mainly in seeds, fruits and other parts such as roots or stems. They are stored in plant cells in the form of oils or waxes.

The next step in the production of vegetable oils is harvesting. 

The harvested oilseed crops must first be cleaned and crushed. 

Once this is done, the next stage of oil production becomes possible, namely…

Oil pressing

This is the production stage during which the fats stored inside the seeds are extracted.

The oil pressing process is possible thanks to so-called oil presses.

Several types of such devices are available on the market:

Oil pressing machines

Screw presses – most commonly used in industry, they press oil using

a rotating screw, ideal for both hot and cold pressing. 

Hydraulic presses – use hydraulic force to extract oil, ideal for producing cold-pressed oils, characterized by higher oil quality. 

Disc presses – use rotating discs to extract oil, used in medium-scale production. 

Solvent extraction presses – use chemical solvents, allow high efficiency, but reduce oil quality. 

What is the difference between cold pressing and hot pressing?

The answer to this question seems quite obvious. 

The key difference is, as one might guess… temperature. 

Contrary to appearances, even in the case of cold pressing, the seeds are heated to about 45°C. Raising their temperature to this level makes it easier to obtain the desired fats while preserving most valuable nutrients such as unsaturated fatty acids (omega-3, omega-6), vitamins (e.g., vitamin E) and antioxidants. 

Thanks to this, the oil retains its full nutritional value and has a beneficial effect on health, supporting the cardiovascular system, immune system and skin.

Hot pressing takes place at temperatures exceeding 100°C.

Under the influence of heating, the seeds become softer, which facilitates the mechanical extraction of oil. 

Plant seeds also contain a certain amount of water, which evaporates as a result of heating, reducing seed moisture. 

Water may hinder the pressing process and reduce its efficiency.

Unfortunately, increasing the pressing temperature leads to the loss of many nutrients and reduces oil quality. This process may also cause the formation of unfavorable compounds such as oxidized fatty acids, which are harmful to health.

Hot-pressed oil often has a less distinct taste and aroma, which is also the result of high temperature. 

During hot pressing, some health-promoting components such as polyphenols, which give oil its characteristic taste and aroma, disappear. 

For those looking for oils full of nutritional and flavor value, hot pressing is less beneficial.

Cold-pressed oils – healthier and tastier

It is therefore easy to conclude that cold-pressed oils are more valuable. They retain not only full flavor but also nutrients – such as brain-beneficial omega acids and vitamins. No wonder such oils are more expensive and their producers can earn more using the same raw material.

Filtration

The final stage of oil production is filtration. 

Filtration ensures that the oil is clean, clear and safe for consumption or further processing. Some oils, especially cold-pressed ones, may remain cloudy or contain small plant residue particles. In such a case, depending on the producer’s preference, the oil may be additionally clarified to obtain a transparent, aesthetically pleasing product.

For effective filtration, among others, plate filters and frame plate filters are used. However, it is easiest to simply choose a ready-made oil pressing and filtration set – you can find it here. Thanks to this, one device allows you to obtain filtered oil ready for consumption or distribution.

Summary – cold-pressed oil vs. hot-pressed oil

Although hot-pressed oils may be cheaper and easier to obtain, their quality in terms of nutritional and health value is lower than that of cold-pressed oils. 

Cold pressing allows most of the oil’s natural properties to be preserved, including valuable vitamins, antioxidants and fatty acids, which is why such oils are considered healthier.

Of course, hot-pressed oils also have their uses, however, if not properly stored, they may contain more harmful compounds such as trans fatty acids or free radicals, so it is worth paying attention to their source and production method.