This separation technique forces a liquid out of a solid matrix using mechanical compression. It is commonly performed using screw presses, hydraulic presses, or roller mills. Unlike solvent extraction, it relies entirely on physical force to squeeze out oils, juices, or moisture, leaving behind a dry cake or meal.
Heard on the job
We need to adjust the screw press because the expression rate on this batch of seeds is running ten percent below target.
Insider tip
Yields are generally lower than chemical extraction methods, but the resulting product is completely free of solvent residues.