Extraction of Lycopenes from Tomato By-Products Using Supercritical Fluids

Importance of the Topic

Supercritical fluid extraction (SFE) of lycopene from tomato by-products addresses the growing demand for efficient, green methods to isolate valuable antioxidants. Lycopene, concentrated in tomato skins, offers health benefits such as cardiovascular protection and is in high demand for nutraceutical and food applications.

Study Objectives and Overview

This work compares supercritical CO2 extraction with traditional Soxhlet acetone/hexane extraction. It aims to demonstrate reduced extraction times, elimination of hazardous solvents, and comparable yield and precision.

Instrumentation Used

• Applied Separations Spe-ed SFE-NP supercritical extraction system
• Spe-ed Matrix packing material (Cat. #7950)
• Spe-ed Wool filters (Cat. #7953)
• Industrial-grade carbon dioxide with dip tube

Methodology and Instrumentation

Sample preparation involved washing and quartering 12 lbs of ripe tomatoes, separating solids, drying at 40 °C for 24 h, and milling to fine powder. The powder was packed between plugs of Spe-ed Wool and mixed with Spe-ed Matrix to minimize void volume. Extraction was performed in a 50 mL vessel under 680 bar and 80 °C, with a CO2 flow rate of 4 L/min for 30 min. Collection was in a pre-weighed amber vial at a valve temperature of 120 °C.

Main Results and Discussion

SFE reduced extraction time from 10 hours to 0.75 hours and eliminated organic solvent consumption. Lycopene recovery reached 96.1% relative to Soxhlet extraction (100%). The slight decrease in recovery is offset by significant gains in throughput and safety. Precision and accuracy were comparable to the reference method.

Benefits and Practical Applications

• Elimination of toxic solvents simplifies regulatory compliance and waste handling
• Substantial time savings improve laboratory productivity
• High-purity lycopene suitable for nutraceutical, cosmetic, and food industries
• Scalable approach for industrial extraction from tomato processing by-products

Future Trends and Potential Applications

Advancements may include continuous-flow SFE systems, integration with in-line analysis (e.g., UV-vis or MS), tuning of co-solvents for selectivity, and development of hybrid extraction technologies. Scale-up studies could enhance commercial viability and support broader applications in natural product isolation.

Conclusion

The study confirms that supercritical CO2 extraction is an efficient, eco-friendly alternative for lycopene isolation from tomato by-products, offering comparable yields to traditional methods while reducing processing time and eliminating hazardous solvent use.

Reference

• Kaziunas A. The Supercritical Carbon Dioxide Extraction of Lycopenes from Tomato Byproducts. Pittcon 2003.
• Khacik F. J. Agric. Food Chem. 1992, 40, 390–398.
• Favati F. Fourth Italian Conference on Supercritical Fluids and Their Applications, 1997, 121–128.