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The present work aims to evaluate the effect of different excitation frequency (200, 500 and 800 Hz) of cold plasma technique as a pretreatment for drying tucumã. SEM images showed changes on the pretreated tucumã's surface, favoring the drying rate and diffusivity of water as well as reducing the drying time. Marginal variation of color and reduced drying time were observed in the samples treated using 200 and 800 Hz. The pretreatment improved the concentration of phenolic (45.3 mg GAE g-1) and antioxidant compounds (799.8 µM ET) (p-value < 0.05). Carotenoids were more sensitive to the drying time, presenting significant degradation at 500 Hz. For this reason, the propose pretreatment based on the application of cold plasma technique for drying foods can preserve/improve their nutritional quality.

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Species of Eugenia have been used as an antidiabetic natural source. Chemical, antioxidant and antiglycant screening of extracts from pedra-ume caá (Eugenia punicifolia) fruits were performed. 1H NMR assisted by non-supervised chemometric methods were employed for the evaluation of the chemical profiles which were distinguished according to the color of fruit maturation stages, as well as for pulp and seed fruit. Furthermore, 1H NMR fingerprint analysis of the crude extract allowed the identification of quercitrin and myricitrin, beside other nine compounds. The extracts of the yellow (YP) and green (GP) pulps presented higher antiglycant and antioxidant activities. Fresh juice from E. punicifolia was encapsulated in microcapsules produced with dextrose equivalent (DE) of 10, 20 or 30 as wall materials for the maintainment of their antioxidant and antiglycant properties. The more efficient retention of the bioactive compounds was found using the DE30. The Encapsulation Efficiency (EE) and the Retention Efficiency (RE) of this system was found around 89.7% and 97.6%, respectively. In addition, NMR spectra revealed the presence of flavonoids O-glycosylated (quercitrin and myricitrin) which might be related to the antiglycant and antioxidant activities. The YP presented larger content of quercitrin (117.6 ±â€¯0.4 mg per each 100 g of fresh fruit). Therefore, pedra-ume caá should be employed as an alternative nutraceutical source, as well as intherapeutic pourposes.

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BACKGROUND: The encapsulated essential oils (EOs) of Piper aduncum L. and Piper hispidinervum C. DC. in gelatin nanoparticles were evaluated against Aedes aegypti Linn., Tetranychus urticae Koch and Cerataphis lataniae Boisd. RESULTS: Encapsulation efficiency of the EOs was measured for absolute concentrations of 500 µg mL-1 (79.2 and 72.7%) and 1000 µg mL-1 (84.5 and 82.2%). The loaded nanoparticles were nearly spherical and well dispersed. The nanoparticles loaded with P. hispidinervum EO had an average size of 100 ± 2 nm, while the nanoparticles containing P. aduncum EO ranged from 175 ± 4 to 220 ± 4 nm. According to zeta potential analysis, the nanoparticles loaded with P. hispidinervum and P. aduncum EOs presented values around -43.5 ± 3 and -37.5 ± 2 mV respectively. The controlled release of EOs was described by the anomalous mechanism of Korsmeyer-Peppas. Both encapsulated EOs reached lethal dosages within 24 h of exposure and total mortality of the tested pests. CONCLUSION: The present work successfully developed gelatin-based nanoparticles that served as carriers for the EOs of P. aduncum and P. hispidinervum to be applied as a sustainable control tool of A. aegypti, T. urticae and C. lataniae. The developed loaded nanoparticles presented high encapsulation efficiency and EO concentration release higher than lethal dosages. This indicates that it is feasible to use gelatin-based nanoparticles loaded with P. aduncum and P. hispidinervum EOs to control the tested pests. © 2018 Society of Chemical Industry.

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Quality parameters of açai juice processed with ultrasound-assisted, ozone and the combined methods were analyzed in this work. Two ultrasound energy densities (350 and 700 J·mL-1) and two ozonization times (5 and 10 min with 1.5 ppm) were analyzed for pure açai juice and 8 different treatments (22 complete factorial). To evaluate the quality parameters of the juice, physical-chemical analyzes such as pH, titratable acidity, cloud value, non-enzymatic browning, rheology, antioxidant activity (DPPH and ABTS), phenolic compounds, anthocyanins, enzymatic activity (peroxidase and polyphenol oxidase) and microbial counts (mesophilic bacteria, molds and yeasts) were conducted. The treatments with ozone were better for microbial inactivation and the ultrasound for enzymatic inactivation. In general, the use of non-thermal methods can be a good alternative for the processing of açai juice.

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The title compound, C(4)H(10)NO(+)·C(5)H(8)NOS(2) (-), is built up of a morpholinium cation and a dithio-carbamate anion. In the crystal, two structurally independent formula units are linked via N-H⋯S hydrogen bonds, forming an inversion dimer, with graph-set motif R(4) (4)(12).