RESUMEN
The migration of plasticizers, i. e., Di-methyl phthalate [DMP] ,Di-[2-ethylhexyl] phthalate [DEHP], Di-n-butyl phthalate [DBF] and Di -ethylhexyl adipate[DEHA] from polyethylene terephthalate bottles [PET] into edible oils [mixture of sunflower oil with soybean oill:l]was studied under temperature of 4, 20 and40+/- 1°C for 360days. The plasticizers were determined by gas chromatography [GC].Statistically significant differences for migration of plasticizers were observed between treatments. Migration of plasticizers depended on temperature and storage time. The results showed that, migration increased with increasing temperature and storage time [contact time].High migration was observed at 40 °C and low migration was found at4 °C. The highest migration level was noticed with DEHA and DEHP compound. The concentration of DEHA and DEHP reached to 1003.42 and 512.41g/ml after 150 and 225 days of storage at 40 °C, respectively. These values were higher than the upper limit for global migration from plastic packaging materials into food and food stimulants set by the European Union [EU] [60mg/kg or 10mg/dm[2]], it could be concluded that, the best storage conditions for edible oils might be 4°C for 6 months or 20 - 40°C for 4 months?
RESUMEN
The results of open-circuit potential and impedance measurements with mechanically polished[MP-],chemically pickled [CP-and anodically covered [AN-] niobium surfaces were found in accord with the implications of the electrochemical theory. MP- electrode yields a surface of open-structure which promotes preferentially the propagation of cathodic and anodic reactions, i.e. the reactivity of surface towards developing a mixed potential. CP-electrode on the other hand, yields apparently surface of much less open-structure due to the formation of an extended surface 61m which can be readily healed up. In contrast from MP- and CP-surfaces, AN-surface [to 5 volt] yields an impervious resistive film which inhibits almost completely the role of the depolarizer, hence the inertness of the surface. The potential acquired by the electrode is far from being characterized as a mixed potential in the sense of the electrochemical theory