Recovery of carotenoids from tomato processing by-products – a review

• Solvent extraction methods for carotenoids recovery from tomato waste are presented.
• Effect of solvent extraction parameters on carotenoids recovery is evaluated.
• Alternative extraction methods include Ultrasound, Microwaves, Enzymes and Pressure.
• Supercritical Fluid Extraction studies for recovery of lycopene are reviewed.

Industrial tomato processing generates large amount of low-value by-products, primarily used as livestock feed or disposed of; however, being a rich source of natural carotenoids, tomato waste can be used to produce high value-added products for food, cosmetics, or pharmaceutical applications. The objective of this review is to summarize and give an overview of the extraction methods available for the recovery of carotenoids and, especially, lycopene from tomato processing by-products. Organic solvent extraction techniques are presented and the effect of extraction conditions on carotenoids recovery is evaluated. In particular, the use of Ultrasound Assisted (UAE), Microwave Assisted (MAE), Enzyme-Assisted (EAE) and Extraction at High Pressure (HPE) for the recovery of carotenoids is assessed. Also, this review examines the efficiency of Supercritical Fluid Extraction (SFE) and in particular the effect of process parameters on carotenoid recovery from industrial tomato waste.