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Abstract: The phase diagrams of PEO1500+sodium tartrate+water, PPO400+sodium tartrate+water, PEO1500+sodium succinate+water, PPO400+sodium succinate+water, PEO1500+sodium citrate+water, PPO400+sodium citrate+water and PPO400+sodium acetate+water aqueous two-phase systems were determined at (283.15, 298.15, and 313.15)K. Both equilibrium phases composition were analyzed by conductimetry and refractive index. In this paper, the influences of polymer hydrophobicity, salt nature and temperature on the phase diagram were analyzed. The phase separation processes was endothermic and the hydrophobic increase make easier the phase splitting, while the electrolyte capacity to induce phase separation follow the order: citrate>tartrate>succinate. The consistency of the tie-line data was ascertained by applying the Othmer–Tobias correlation. The experimental data were correlated with the NRTL model for the activity coefficient, with estimation of new interaction energy parameters. The results, analyzed in terms of root mean square deviations between experimental and calculated compositions, were considered satisfactory. [Copyright &y& Elsevier]

Sugarcane bagasse cellulose mixed ester succinate phthalate (SBSPh) was synthesized by a novel one-pot reaction method. The effects of temperature, time and mole fraction of succinic anhydride (χ SA ) on the responses weight gain (wg), number of carboxylic acid groups (n T,COOH ), and adsorption capacity (q) of Co 2+ and Ni 2+ were evaluated by a 2 3 experimental design. The chemical structure of the material was elucidated by Fourier transform infrared, 13 C Multiple Cross-Polarization solid-state NMR spectroscopy and 1 H NMR relaxometry. The best SBSPh synthesis condition (100 °C, 11 h, χ SA of 0.2) yielded a wg of 59.1%, n T,COOH of 3.41 mmol g -1 , and values of q Co 2+ and q Ni 2+ of 0.348 and 0.346 mmol g -1 , respectively. The Sips model fitted better the equilibrium data, and the maximum adsorption capacities (pH 5.75 and 25 °C) estimated by this model were 0.62 and 0.53 mmol g -1 for Co 2+ and Ni 2+ , respectively. The Δ ads H° values estimated by isothermal titration calorimetry were 8.43 and 7.79 kJ mol -1 for Co 2+ and Ni 2+ , respectively. Desorption and re-adsorption efficiencies were evaluated by a 2 2 experimental design, which showed that SBSPh adsorbent can be recovered and reused without significant loss of adsorption capacity., (Copyright © 2018 Elsevier Inc. All rights reserved.)

There is an increasing tendency to add natural antimicrobials of plant origin into food. The objective of this work was to develop a microbial sachet incorporated with allyl isothiocyanate (AIT), a volatile compound of plant origin, and to test its efficiency against growth of yeasts and molds, Staphylococcus sp. and psychrotrophic bacteria on sliced mozzarella cheese. Another objective was to quantify the concentration of AIT in the headspace of cheese packaging. A reduction of 3.6 log cycles was observed in yeasts and molds counts in the mozzarella packed with the antimicrobial sachet over 15-day storage time. The sachet also showed an antibacterial effect on Staphylococcus sp., reducing 2.4 log cycles after 12-day storage. Psychrotrophic bacteria species were the most resistant to the antimicrobial action. The highest concentration of AIT (0.08µg.mL(-1)) inside the active packaging system was observed at the 6(-)day of storage at 12 ºC ± 2 ºC. At the end of the storage time, AIT concentration decreased to only 10% of the initial concentration. Active packaging containing antimicrobial sachet has a potential use for sliced mozzarella, with molds and yeasts being the most sensitive to the antimicrobial effects.