Development of a stable free-flowing powder lycopene formulation via particle engineering using supercritical carbon dioxide

Abstract: Tomato processing industry generates large amounts of waste in the form of tomato peel and seed that contain lycopene – a high-value bioactive compound. However, isolation of lycopene from the waste and conversion into a useful form is challenging − requires use of hazardous and toxic solvents, and lycopene degrades easily in the presence of light and oxygen. Therefore, there is a need for simple, efficient, and clean methods to convert lycopene into easy-to-use and stable forms to transform tomato waste into a useful form to improve human health and food quality.

The objective of this study was to obtain a lycopene-rich oleoresin from tomato processing waste and to convert it into a stable free-flowing powder form using a green approach based on supercritical fluid technology. Lycopene-rich oleoresin was extracted from tomato waste and then loaded into hollow solid lipid micro- and nanoparticles (HoSoLiP) using an innovative green particle formation method based on supercritical carbon dioxide. The performance of the products was determined via storage test by determining oxidative and physical stability, melting behavior, polymorphism, and color.

During one-month storage at 4 °C, 84.7% of the lycopene in the original oleoresin degraded, whereas 17.5% degraded in the HoSoLiP. At room temperate (22 °C) for one month, the lycopene loss was 88.0%, while it was 26.8% in the HoSoLiP. Moreover, there was no change in the particle morphology, polymorphic form, melting behavior, and color after one-month of storage at room temperature.

This is a simple and green approach (no solvent is used, and no waste is generated) that generates high-value, “natural” and stable lycopene product from industrial waste. The novel particles are alternatives to emulsions using high-energy methods or complicated chemical processes. The powder form makes handling, storage, and transportation convenient; most of the current lipophilic bioactive delivery systems are liquid.