This research involves experimental studies of supercritical fluid (SCF)-based micronization and encapsulation processes exploiting both solvent and antisolvent properties of supercritical CO2 for diverse functional pigments to extend the application of these natural functional pigments. First, the reliability of homemade experimental apparatuses designed and constructed by our research group was tested. Quercetin and β-carotene were used as model substances in the micronization process via supercritical antisolvent (SAS). Bixin-rich extract with polyethylene glycol (PEG) 10,000 as encapsulant material was used in the encapsulation process via SAS, while rutin and anthocyanin-rich extract with PEG 10,000 and ethanol as cosolvents were applied to the formation of polymeric microcapsules via rapid expansion of supercritical solutions (RESS). The processing parameters and the used levels were based on the literature data. SAS process successfully reduced the particle size of quercetin by 4.1 times, while conventional micronization process only reduced the particle size by 1.8 times. Furthermore, it was demonstrated that SAS process can be successfully utilized to coprecipitate microparticles of PEG loaded with bixin-rich extract. RESS process using ethanol as cosolvent was employed effectively to encapsulate rutin and anthocyanin-rich extract in the PEG matrix. The data obtained in this study are in good agreement with the previous values reported by several authors using similar operational conditions and equipment. Core material: encapsulant material ratio, core material physical properties, such as solubility in supercritical CO2 and in CO2 + ethanol, and viscosity were key parameters for these processes. PRACTICAL APPLICATIONS The application of natural food colorants with relevant antioxidant activities, such as carotenoids and flavonoids, as food additives in various food products is seriously hampered by their fast degradation triggered by light, temperature, presence of oxygen, insolubility in aqueous systems and low dispersibility, among others. Their particle size reduction and/or encapsulation have been successfully used to overcome all these drawbacks. SCFs have become an attractive alternative solvent due to their environmentally friendly properties. SCFs may be conveniently used for various applications such as extraction, reactions, micronization and encapsulation, among others. 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