Abstract

In this paper an innovative process for the extraction of pure lycopene from tomato-waste in water that uses the Extractor Naviglio^® and water as solvent is presented. The use of water as extracting solvent considerably reduces the cost of the entire process if compared with the commonly used solvent-based procedure or with the newer supercritical extraction process of lycopene from tomato-waste. Exhausted tomato-waste treated with water can be then easily dried at room temperature and further used, e.g. in agriculture or as food ingredient in animal nutrition. Lycopene, not soluble in water, was recovered in a quasi-crystalline solid form and purified by SPE (Solid Phase Extraction) using a small amount of organic solvent. The alltrans lycopene was obtained at a very high grade of purity, not less than 98% (w/w), with an average recovery from tomato waste of 14% (w/w). The availability of high purity all trans lycopene allowed us also to measure the molar absorption coefficient, unique for each molecule. An alternative procedure for the HPLC analysis, that uses a phenyl-hexyl silicone stationary phase as inverse phase and a linear gradient in water and acetonitrile, is also described.

Key words: Lycopene, Extractor Naviglio^®, tomato-waste, HPLC-Diode array, solid-liquid extraction, chromatography, solid phase extraction.