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This work aimed to study the kinetics of bifenthrin and deltamethrin residues degradation in rice grains under exposure to ozone and evaluate the effect of ozonization on rice grains marketing standards. The grains sprayed with pesticides were exposed to ozone at a concentration of 3 mg L and continuous flow of 1.0 L min for defined periods of up to 10 h. Residues of pesticides were extracted from grains using solid liquid extraction method with low-temperature partition analyzed by gas chromatography with electron capture detection (SLE/LTP-GC/ECD). Data from residual concentrations of bifenthrin and deltamethrin, due to the ozone exposure period, were adjusted to kinetic models of zero order, first order and second order. It was observed that ozone was effective in the degradation bifenthrin and deltamethrin residues, removing 91.9% of bifenthrin and 92.7% of deltamethrin. The kinetic model that best fitted deltamethrin and bifenthrin residues degradation data by ozone, was the one of first order. The marketing standards evaluated were the water content and yield. It was observed the ozone did not alter the rice grains water content and yield.

This study investigated the effect of a drying method with intermittent ratios on the effective drying time, specific energy consumption and essential oil yield of clove basil (Ocimum gratissimum L.) leaves. The drying tests were conducted at the Postharvest Laboratory of Medicinal, Aromatic and Condiment Plants, from the Departamento de Engenharia Agrícola of the Universidade Federal de Viçosa, Viçosa, MG, Brazil (20° 46’ 13.5” S; 42° 52’ 23.3” W, and altitude of 645 m) in October and November 2017. The experiment was conducted by using a 3 × 4 factorial scheme including three drying temperatures at 50, 60 and 70 °C, with four drying processes: continuous drying and the following three intermittent drying/tempering ratios in minutes: 10/20, 15/15 and 20/10. The design was completely randomized and with three repetitions. The application of the 10/20 intermittent ratio reduced the effective drying time and the specific energy consumption. Regarding the essential oil yield, the use of the intermittence presented different results for each temperature of drying; the highest yields were observed with continuous drying at 50 °C and drying with the 20/10 intermittent ratio at 60 °C. The results indicate that intermittent drying at 50 °C is not recommended to preserve essential oil yields.

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Mikania laevigata leaves are used worldwide as herbal medicines. Our study investigates the production differences among three different genotypes of this herb: the genotypes' influence on the essential oil yield, chemical composition, and the plant tissues involved in the secretion of the chemical compounds produced by the leaves. The study performed the analysis during the summer and winter seasons. Plants were grown under an organic cultivation system in Oratórios, Minas Gerais, Brazil. Essential oils were extracted by hydrodistillation and analyzed by gas chromatography/mass spectrometer. The analysis highlighted substantial genetic variability among the genotypes. The genotype CENARGEN showed higher biomass production, oil yield, and a high concentration of major constituents detected by chromatographic analysis in essential oils, such as germacrene D and caryophyllene oxide. The season affected the chemical composition of the essential oils. Germacrene D and bicyclogermacrene were the major constituents in the winter-essential-oils; spatulenol and caryophyllene oxide were the major constituents in the summer-essential-oils.