Automatic extraction systems facilitate separation of a substance from a matrix. Extraction methods include liquid-liquid extraction, and solid phase extraction. Rapid Soxhlet extraction systems can be used in nearly every analytical area. The patented fully automated extraction process is especially useful for residue analysis and the determination of fat in food and feed samples (solid-liquid extractions according to Soxhlet and Twisselmann). Devices are available that conform to international and national norms and extraction standards.