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Nowadays, cinnamon essential oil has been considered as an antioxidant and antimicrobial activity for addition to food and biological systems. Directly use of these essential oil for food storage has some limitations due to low solubility in water, high vapor pressure and pHysical and chemical instability. One of the ways to reduce these limitations is the microencapsulation of essential oils in lipid carriers, including microcapsules. Therefore, the aim of this work was to study the encapsulation of cinnamon essential oil in microcapsules stabilized with sodium caseinate and β-cyclodextrin and also the antimicrobial and antioxidant properties. In this study, in order to encapsulation, different formulations of nano emulsions containing cinnamon essential oil were prepared by ultrasound method and the effect of different polymers on droplet size, encapsulation efficiency, antioxidant properties and turbidity of nano emulsion were investigated. The results showed that the interaction of nano emulsions and encapsulated samples was effective on particle size (p <0.05). The diameters of sodium caseinate with β -cyclodextrin particles size ranged from 234 to 237 nm. Also, the diameter of the β -cyclodextrin particles in the range of 713-717 nm, and the diameter of the essential oil particles size in the range of 84-85 nm. Zeta potential was negative for sodium caseinate with β -cyclodextrin and essential oil. That showed the system had a significant negative charge. The effect of different polymers and essential oil on the encapsulation efficiency and antioxidant properties was significantly different. (P <0.05). The encapsulation efficiency of all formulations was above 70%. SEM-scanning showedhomogeneous and spHerical shapes with pores.FT-IR analysis confirmed the effect of van der waals forces in the formation of microcapsules. [ABSTRACT FROM AUTHOR]

Today, Melissa essential oil has been drawn a lot of attention in food researches. This essential oil has good antioxidant and antimicrobial activity, so it is a good candidate to incorporate in the nutritional and biological systems. The aim of this study was to investigate the release of Melissa essential oil (encapsulated via isolated proteins and sodium caseinate) in yoghurt by dispersive liquidliquid microextraction (DLLME) /gas chromatography technique. In this study, yogurt samples with different percentages of essential oil (0, 0/75, 1/5 g/l) were prepared by sonication method. The effect of two factors, including storage time (1, 11, 21 days) and the percentage of encapsulated essential oil on the gas chromatography profile were studied based on the central composite design (CCD). 10 grams of yogurt samples containing various percentages of essential oil was centrifuged and the liquid part was passed through a sterilization filter. The released essential in the yogurt was extracted (from the liquid part) by DLLME method and was injected into the gas chromatography and its chromatographic profile (total peak area and total peak height) was investigated. The results show that there is a significant relationship between the total peak area and the amount of essential oil released into the yogurt. By studying total peak area in chromatography, it is possible to estimate the amount of essential oil released into the yogurt sample, and it is possible to study the rate of release. [ABSTRACT FROM AUTHOR]

In this study, the parameters affecting the synthesis of silver nanoparticles were optimized by green chemical reduction method to make a conductive pattern. The raw materials used in this study, include silver nitrate as a source of silver ions, polyvinylpyrrolidone as surface stabilizer, and glucose as the reducing agent. Effective parameters were investigated by Taguchi statistical design, to determine the optimum conditions and achieve the smallest average particle size. Silver nanoparticles were characterized by X-ray diffraction and field emission scanning electron microscopy. The smallest particle size can be applied by solution adding rate of 0.1 ml/min, temperature 90 °C, weight ratio of glucose to silver nitrate 3 g/g and weight ratio of Polyvinylpyrrolidone to silver nitrate 3.2 g/g. According to.our expectation 20 nm silver nanoparticles were obtained in this condition. FE-SEM confirmed the above results and showed nanoparticles with a size of 25 nm. Finally, A conductive pattern was printed on a glass substrate with synthesized powder. The electrical resistance of the printed pattern was 0.088× 10-4 Ω.cm. [ABSTRACT FROM AUTHOR]