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The effects of supercritical CO2 processing on the chemical stability of fructooligosaccharides (FOS) and other functional and nutritional compounds were evaluated employing non-thermal and thermal approaches. Apple juice was enriched with Pfaffia glomerata roots aqueous extract due to its high content of short-chain FOS and then subjected to different levels of temperature (40 and 60 °C), pressure (8 and 21 MPa), and CO2 volume ratio (20 and 50%). The percentage of CO2 volume was evaluated concerning the total volume of the high-pressure reactor. Also, the functional beverage was thermally treated at 105 °C for 10 min. Physicochemical properties (pH and soluble solid content), beta-ecdysone, sugars (glucose, fructose, and sucrose), and FOS (1-kestose, nystose, and fructofuranosylnystose) content were determined. The pH and soluble solid content did not modify after all treatments. The pressure and CO2 volume ratio did not influence the FOS content and their chemical profile, however, the temperature increase from 40 to 60 °C increased the nystose and fructofuranosylnystose content. High-temperature thermal processing favored the hydrolysis of 1-kestose and reduced the sucrose content. Regarding beta-ecdysone, its content remained constant after all stabilization treatments demonstrating thus its high chemical stability. Our results demonstrated that supercritical CO2 technology is a promising technique for the stabilization of FOS-rich beverages since the molecular structures of these fructans were preserved, thus maintaining their prebiotic functionality.

This paper presents novel outcomes about the effect of degree of inulin polymerization (DP) on the technological properties of annatto seed oil powder obtained by freeze-drying. Inulins with two DP's were evaluated: GR-inulin (DP≥10) and HP-inulin (DP≥23). Micrographs obtained by confocal microscopy were analyzed to confirm the encapsulation of bioactive compounds using both inulins, especially the encapsulation of the natural fluorescent substance δ-tocotrienol. Microparticles formed with both inulins presented the same capacity for geranylgeraniol retention (77%). Glass transitions of microparticles formed with GR-inulin and HP-inulin succeeded at 144°C and 169°C, respectively. Regarding water adsorption isotherms, microparticles formed with HP-inulin and GR-inulin presented behaviors of Types II (sigmoidal) and III (non-sigmoidal), respectively. Reduction of water adsorption capacity in the matrix at high relative moistures (>70%) was presented when HP-inulin was used. At low relative moistures (<30%), the opposite behavior was observed.

In this study, coupling of ultrasound (US) device and rotor-stator (RS), operating at low-energy densities, was studied as an alternative process to individual US and RS to produce modified starch-stabilized oil-in-water emulsions, as well as its potential use to encapsulate eugenol. To this aim, a full factorial design was employed to evaluate the effects of the US nominal power (0, 360 and 720 W) and RS nominal power (0, 150 and 300 W) on the physical properties, encapsulation efficiency and kinetic stability of emulsions produced. Firstly, the action of modified starch and eugenol onto interface oil-water was evaluated. The emulsifier was rapidly adsorbed on the interface water-sunflower oil reducing the interfacial tension from 25 to 16 mN/m, while eugenol did not show surface activity. The increase of energy density, in general, resulted in droplet size reduction, indicating the relevant role of the forces involved in the droplet breakup on emulsion stability. Coupling was more efficient on the droplets breakup producing smaller droplet size with narrower size distribution. While the coupled system work during 5 min for an energy density of 583 J/mL, the corresponding emulsification time for operating singly US and RS were 7.09 min and 17.04 min, respectively. Therefore, the main advantage associate to coupled process is the reduction of processing time to produce an emulsion with better kinetic stability.

This work aimed to study the microencapsulation of anatto seed oil using inulins with two degree of polymerazation (DP), GR-inulin (DP ≥ 10) and HP-inulin (DP ≥ 23), as wall material. The microparticles obtained by freeze-drying (FD) were caracterized with respect to scanning electron microscopy (SEM), confocal scanning laser microscopy (CSLM), encapsulation efficiency (EE) and differential scanning calorimetry (DSC). The DP's had not influence on the physicalchemical properties of microparticles. However, were produced novel additives for food industry with functional and therapeutic properties.