How Sunflower Seeds Are Processed into Oil: Key Technologies and Their Differences

Sunflower oil does not come directly from the seeds immediately after pressing. There is an entire production process between the sunflower seeds and the finished product: cleaning of raw materials, seed preparation, oil extraction, filtration, and, if necessary, refining.

The choice of technology depends on the quality of the raw materials, the equipment's capacity, and the requirements for the finished oil.

How are sunflower seeds turned into oil?

In industrial production, the seeds are first cleaned to remove soil, stones, plant debris, and other impurities. Next, their moisture content and oil content are checked, and, if necessary, they are sorted by size, hulled, and ground.

After preparation, the oil is extracted using one of the following main methods:

seeds → cleaning → preparation → pressing or extraction → filtration → purification/refining → finished sunflower oil.

It is precisely during the oil extraction stage that the main differences between the technologies become apparent.

1. Cold pressing

When cold pressing The seeds are mechanically ground and pressed in a screw press without any targeted, intense heating.

The result is unrefined oil, which, after settling and filtration, retains the characteristic flavor, aroma, and color of the original seeds.

However, the term «cold pressing» does not mean that the oil’s temperature always remains low during the process. Due to pressure and friction, the temperature can rise and depends on the press’s design, the moisture content of the raw materials, and the operating conditions.

A recent study from 2026 showed just how much seed characteristics influence the efficiency of cold pressing: for oilseed hybrids, the oil extraction efficiency was 41,63–75,61%, and for confectionery hybrids—only 20,10–48,40%.

2. Hot Pressing

When hot pressing Before mechanical extraction, the seeds undergo additional heating or conditioning.

Heat treatment alters the structure of the raw materials and facilitates oil extraction. Therefore, this technology is typically geared toward higher productivity and the efficient use of oilseeds.

After pressing, the oil is separated from the oilcake and may be sent for filtration, hydration, and further refining, depending on the product's intended use.

Thus, cold and hot pressing differ primarily in that the raw material preparation process, temperature treatment, oil yield, and the characteristics of the resulting product.

3. Solvent extraction

At large oil and fat processing plants, the following is also used: solvent extraction.

After mechanical pressing, a certain amount of oil still remains in the oilcake. During extraction, the solvent removes the residual fat from the prepared material.

The advantage of this method is its high oil extraction rate. In an experimental study using a twin-screw extruder, the combination of thermomechanical treatment and extraction resulted in up to 98% oil extraction, while the residual oil content in the oilcake was less than 3% under specific, predetermined conditions.

Important: These values are the results of a specific study and do not represent a universal standard for any industrial line.

4. Combined Technology

In practice, the following approach can be used: pressing + extraction.

First, the press mechanically removes most of the oil. The resulting oilcake is then subjected to further extraction.

This approach allows for more efficient use of raw materials and reduces the amount of oil remaining in the oilcake.

That is precisely why large industrial enterprises choose a technology not only based on the principle of «which oil is better,» but also by taking into account oil yield, throughput, energy consumption, and processing costs.

What factors affect sunflower oil yield?

There is no single figure that applies to all sunflower seeds.

The following factors affect output:

• seed oil content;
• moisture content of raw materials;
• variety and hybrid;
• the size and contents of the shell;
• storage conditions;
• degree of grinding;
• preparation temperature;
• screw pressure and speed;
• residual oil in the oilcake.

For example, a 2026 study on cold pressing showed that The oil content of the seeds and the weight of the raw material fed into the system are among the most significant factors, which determine the effectiveness of the pressing process.

Which technology is better?

Each technology has its own purpose.

Cold pressing Suitable for products where natural characteristics and minimal processing are important.

Hot Pressing is designed to improve mechanical extraction efficiency and industrial productivity.

Extraction allows you to make the most of the oil remaining after mechanical processing.

Combined Technology combines the advantages of pressing and the subsequent extraction of oil from the oilcake.

Therefore, it cannot be said that one method is the best in all cases.

What happens to the oil after it is extracted?

Raw pressed oil contains fine particles of raw material and impurities. Depending on its intended use, it may undergo settling, filtration, hydration, neutralization, bleaching, and deodorization.

Refined sunflower oil undergoes a more thorough purification process, whereas unrefined oil may retain more of the characteristic properties of the original seeds.

International Standard Codex Alimentarius CXS 210-1999 sets forth requirements for the specified vegetable oils, including sunflower oil. The document was adopted in 1999 and has been revised and updated on numerous occasions.

Bottom line

The process from sunflower seed to a bottle of oil involves several production steps. The main extraction methods are— cold pressing, hot pressing, extraction, and combined processing.

For a manufacturer, equipment is not the only key factor. The quality and oil content of sunflower seeds directly affect oil yield, line productivity, and the economics of processing.

Therefore, efficient production begins with the right choice of raw materials and ends with quality control of the finished oil.