Solvent extraction system suitable for the separation of a substance or a group of elements from solid and semi-solid samples according to the Randall technique. The solvent extractor SER 148 can be used to separate a substance or a group of elements (e.g. fat extraction) from solid and semi-solid samples according to the Randall technique (consisting of immersion, washing and solvent recovery), the evolution of the traditional Soxhlet extractor, by using solvents. This technique offers three great benefits over the Soxhlet technique: - up to 5 times faster than Soxhlet (hot solvent vs. cold solvent) - low solvent consumption (high solvent recovery) - limited cost per analysis In addition, the SER 148 offers full operator safety in compliance with IP55. The main field of application is the determination of the content of soluble products such as fats, detergents, plasticizers and pesticides in food, animal feeds, detergents, rubber and plastic formulas, pharmaceutical products, soil, etc.