Ultrasound Assisted Extraction of Oil from Tomato Seeds

Approximately 10–30% of tomatoes are wasted during processing. Tomato pomace consists of crushed skin and seeds of tomatoes. Seeds might be considered as a potential source of vegetable oil. Tomato seeds contain about 20% oil with a fatty acid composition similar to that of low linolenic soya bean oil. Different novel techniques of extraction are being explored such that the rate of extraction, the yield may be increased and quality retained. Novel extraction methods may consist of ultrasound-assisted extraction, microwave-assisted extraction, supercritical fluid extraction, pressurized liquid extraction etc. Of these Ultrasound-assisted extraction has been found to be an inexpensive, simple and effective method of extraction. The main advantages are increased extraction yield and higher kinetics compared to conventional extraction techniques, soxhlet method. Ultrasound might also be operated at lower temperature of operation helping to extract the heat-sensitive compounds. The extracted oil after purification/refining may be employed for consumption. The objective of the present study was to evaluate the extraction yield of tomato seed oil using power ultrasound at different acoustice energy density, temperatures and treatment time. The qualities of the extracted oil such as free fatty acid have been evaluated.