This work reports experimental phase equilibrium (transition points) data for the systems CO 2 + ethyl acetate, CO 2 + ethyl acetate + β-carotene, and CO 2 + ethanol + β-carotene at different concentrations of β-carotene in the organic (liquid) solvents. For this purpose, the static synthetic method, using a variable-volume view cell, was employed for obtaining the experimental data in the temperature range from (303 to 343) K and pressures up to 12 MPa. Vapor-liquid phase transitions were observed as bubble and dew points for all overall compositions investigated. In a general sense, it was experimentally observed that the addition of β-carotene leads to negligible changes in pressure transition values compared to CO 2 + solvent systems. The Peng-Robinson equation of state, with the classical van der Waals quadratic mixing rule, was employed for the thermodynamic modeling of the systems investigated with a satisfactory agreement between experiment and theory. It was also observed that the interaction parameters of β-carotene/organic solvent and β-carotene/CO 2 need not be considered for efficient prediction of phase behavior of the ternary systems.

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The study evaluated a QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction method for use with a TLC quantification procedure for deoxynivalenol (DON). It also surveyed DON occurrence in wheat flour from the southern region of Brazil. Forty-eight wheat flour samples were analysed, divided into 2 different harvest lots, each consisting of 24 different brands. The detection and quantification limits of the method were 30 and 100 ng of DON on the TLC plate. The various concentrations of DON presented high linearity (R = 0.99). A negative matrix effect (-28%) of the wheat flour was verified, with suppression of the chromatographic signal of DON, and 80.2-105.4% recovery. The TLC method was reliable for DON evaluation, with a coefficient of variation of less than 10%. High-performance liquid chromatography of lot 2 samples confirmed the presence of DON in all samples identified DON-positive by the TLC technique. Of the 48 wheat flour samples in lots 1 and 2 analysed by TLC, 33.3 and 45.8% of the samples respectively were above the Brazilian legislation limit. Correlations were observed between the water activity and DON content, and between the fungal count and moisture content of the wheat flours.

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In this study, the extraction yield, the mathematical modeling of pressurized liquid extraction (PLE) kinetics with sub-and supercritical carbon dioxide (SC-CO 2 ) of olive leaves (Olea europaea) and the biological activity of the extracts were evaluated. The extraction with PLE was conducted isobarically (10.3 MPa), varying the temperature (20, 40 and 60 °C) and the solvent (ethyl acetate, acetone, ethanol, ethanol:water-80:20, v:v), solvent flow (2 mL min -1 ) and time (110 min) and the extractions with SC-CO 2 , varying the temperature between 20 and 60 °C and the pressure between 8 and 25 MPa, keeping the time constant (210 min) and the CO 2 flow of 2 mL min -1 . In the extracts, antioxidant activity, total phenolic and flavonoid contents and oleuropein were evaluated. The highest total extract yield in the PLE was 30.91% at 60 °C, 10.3 MPa using ethanol:water (80:20, v:v). The yield obtained using the supercritical fluid was 0.68% at 60 °C and 25 MPa. The PLE extract obtained with ethanol at 60 °C presented the highest concentration of total phenolic content (386.42 mg GAE g -1 extract), total flavonoids content (33.43 mg CAT g -1 extract), oleuropein (73.65 mg g -1 extract) and antioxidant activity (82.87%). The overall extraction curves were modeled using the well-established Sovova ´model and kinetic extraction model based on the Brunauer-Emmett-Teller theory of adsorption. Both kinetic models used were able to correlate well with the experimental data with slightly better results obtained by the former. The alternative PLE extraction technique investigated in this work was found to be suitable for the extraction of olive leaves after short times of extraction obtaining an extract with high biological activities.