Table 1.

Extraction methods for recovering lycopene from TBPs: advantages and disadvantages.

	Extraction Method	Main Features	Advantages	Disadvantages
	Classical organic solvent extraction (COSE)	solubilization of the components of interest into organic solvent/s added to the plant matrix	easily modifiable parameters (i.e., ratio solvent/matrix, temperature, extraction time) large production capacity easy continuous operation	long process time toxicity of solvents traces that can remain downstream purification operations high environmental impact high health risks (i.e., use of highly flammable and/or toxic solvents)
Pretreatments before COSE	Pulsed electric fields treatment	application of electric field pulsing on plant matrices that induces electropermeabilization	high extraction yields no thermal effect low operation cost short process time no isomerization or degradation	dependence on medium composition (conductivity) high cost of the equipment
	Enzyme-assisted extraction	use of enzymes catalyzing the hydrolytic cleavage of structural components of the cell wall of the waste product	high extraction yields reduction in extraction time reduction in using organic solvent high selectivity	high enzyme cost currently available enzymes cannot hydrolyze cell walls completely difficulty of enzyme recovery high dependence on pH, temperature, metal ions, etc.
	Supercritical fluid extraction	use of supercritical fluids as the extracting solvents to separate component/s from the matrix	eco-friendly method high purity low operating temperatures (no thermal degradation) free of organic solvents’ residues fast and high yield high selectivity	high power consumption very expensive and complex equipment elevated operating pressures consistency and reproducibility may vary in continuous production 1
	Ultrasonic-assisted extraction	the ultrasound waves cause a mechanical impact, allowing greater penetration of the solvent into the plant body (“sponge effect”)	eco-friendly method high efficiency low energy consumption low equipment cost high extraction yields reduction in extraction time harmless use of small amount of organic solvents	scale-up not feasible possible degradation of thermolabile compounds highly reactive free radical generation low selectivity limited extraction volumes lack of uniformity in the distribution of ultrasound energy
	Microwave-assisted extraction	microwaves heat solvents that contain samples, thereby partitioning analytes from the matrix into the solvent	eco-friendly method reduced use or no use of organic solvents possibility to avoid thermal degradation short extraction times high extraction yields	difficult to scale up potential risk of explosion in case of closed vessel operating conditions limited extraction volume high costs of microwave set-up limited choice of the extraction solvents
	Microemulsion technique	formation of thermodynamically stable dispersion of two immiscible liquids in the presence of surfactants (microemulsions) that improve the solubilization capacity of both liquids	high extraction yields ease and economical scale-up efficient at room temperature short extraction times reduced use or no use of organic solvents stability against oxidation	surfactants could be risky for health phase inversion microemulsions could require development of complex systems that may be time-consuming
	Water-induced hydrocolloidal complexation	formation of lycopene and pectin colloidal complexes in an aqueous environment that can be recovered by sedimentation or centrifugation	small amount of organic solvents high selectivity high purity	need of a subsequent recovery step extraction yield comparable to that of classical organic solvent extraction

¹ see Reference [35].