Hemp Seed Oil Extraction/ pressing

Hemp seeds contain around 25-35% fat. Cold pressing results in a fatty-acid-rich hemp seed oil, with approximately 65% of the oil in the seeds being extracted. This mechanical method can be performed with whole or dehulled hemp seeds using a screw press or hydraulic press, applying pressures of up to 500 bars. Heating the seeds to a temperature of 50-70°C can increase the amount of oil extracted; however, this may denature the proteins, making the press cake less desirable for protein extraction. The remaining hemp press cake, which contains about 35% of the initial oil content (8-15% total), can be further used as raw material for hemp protein powder or animal feed.

In addition to mechanical extraction, methods such as solvent-based extraction can yield a higher percentage of extracted oil. However, these methods have several downsides, including environmental hazards, the potential for toxic residues, and higher costs. After solvent-based extraction, the remaining residues are referred to as hemp meal.

After extraction, the oil needs to be filled into containers to avoid oxidation due to its high amount of unsaturated fatty acids. This is performed under a nitrogen atmosphere to prevent exposure to oxygen.