Effect of extraction parameters on the carotenoid recovery from tomato waste

P>Tomato waste is an important source of natural carotenoids. This study was carried out to assess the extractability of tomato waste carotenoids in different organic solvents and to optimise the extraction parameters (type of solvent, extraction time, temperature and extraction steps) for maximum yield. Among other solvents, we tested a new environmentally friendly one, ethyl lactate, which gave the highest carotenoid yield (243.00 mg kg-1 dry tomato waste) at 70 degrees C, compared to acetone (51.90 mg kg-1), ethyl acetate (46.21 mg kg-1), hexane (34.45 mg kg-1) and ethanol (17.57 mg kg-1). The carotenoid recovery was significantly (P < 0.05) affected by the number of extraction steps and temperature in all solvents. Mathematic equations predicted rather satisfactorily (R2 = 0.89-0.93) the rate of carotenoid extraction in the above-mentioned solvents. Carotenoid concentration increased with time, approaching a quasi-saturated condition at approximately 30 min of extraction.