Iranian Journal of

Background and Objective: Aluminum (Al) is a neurotoxic agent and this element is being associated with Alzheimer disease. The use of semi-rigid packaging has been increased in recent years. In these packages, the main layer is aluminum. The purpose of this study was to determine the Al concentration in foods packaged in semi-rigid packaging in during storage time.
Materials and Methods: Al concentration of the samples (Joje kabab, khorake morgh, khoresh gheymeh, n=36) was determined at different storage times (0, 60, 120, and 180 days after packaging). Aluminum was determined by ICP-OES after wet digestion method of the samples. A two-way analysis of variance was used to analyze the results with respect to time and food factors.
Results: The effect of storage time on Al concentration was significant p˂0.001. The samples that were stored longer had significantly higher aluminum concentrations. The highest concentration was determined in Joje kabab (3.27 ±0.93 ppm( and lowest Al content was determined in khoresh gheymeh (1.04 ± 0.16 ppm). The results showed that Al concentration of the foods packaged in semi-rigid packaging increased significantly during storage.
Conclusion: Considering the present state of knowledge and the suggested provisional tolerable daily intake of 1 mg/kg body weight per day of according to World Health Organization, Al leaching from semi-rigid packages may add low doses of Al into the diet.
 

Background and Objective: Natural antimicrobial compounds have a valuable capacity to be used in a variety of foods to inhibit growth of foodborne pathogens and spoilage bacteria. The aims of this study were to produce active biodegradable films by incorporation of different percentage of oregano essential oil (OEO) and ethanolic extract of propolis (EEP) into poly-lactic acid (PLA) films, and to evaluate physical and antimicrobial properties of the resulting films. 
Materials and Methods: The active films were produced by solvent casting method, and their thickness and major color parameters were measured using a digital micrometer and a colorimeter instrument, respectively. Afterwards, antibacterial effects of the films were assessed against four common foodborne pathogens, including Staphylococcus aureus, Escherichia coli, Vibrio parahaemolyticus and Listeria monocytogenes, by means of disk diffusion test.
Results: Physical examinations showed that thickness of resultant films significantly was increased (p<0.05) by addition of different concentrations of active agents. Additionally, the presence of them in the structure of films decreased the lightness and increased the redness and yellowness, simultaneously.  While none of the neat PLA film or films with just EEP had no antibacterial effect, all films containing higher percentages of OEO (5 and 10%) were effective against all four tested bacterial strains, and these effects were more significant in case of the gram-positive bacteria. The maximum inhibition zone was recorded for the film containing 10% of OEO and 2% of EEP, which the relevant values were 56.66, 45.46, 17.91 and 17.65 mm for Staphylococcus aureus, Listeria monocytogenes, Vibrio parahaemolyticus and Escherichia coli, respectively.
Conclusion: Based on the findings of this study, the presence of just EEP in the initial formulation of poly-lactic acid films was not effective against the four tested foodborne pathogens, while the addition of this compound to the films containing OEO increased the effective antibacterial properties of the resulting films. As a result, the simultaneous use of these two compounds in the structure of hydrophobic films, such as poly-lactic acid film, can be used to produce active food packaging films.
 

Background and Objective: Today with progress and improvement of knowledge of human in the food industry field, plastic coatings owing to their unique properties, is extensively applied for a package of beverages and food like water and milk. Phthalate esters (PAEs) are applied to increase e sustainability, efficiency and flexibility of materials. Chronic exposure to stated compounds has a role in the occurrence of several types of human illnesses and cancer. The purpose of this study is to investigate the presence and amount of phthalate esters in different types of milk supplied in Tehran city by using magnetized nanotube crane with magnetic iron oxide and through GC-MS device.
Materials and Methods: In this research, multi-walled magnetic carbon nanotubes were synthesized by applying iron oxide and then synthesized magnetic nanotubes were applied for absorption and extraction of PAEs from the matrix of milk samples. The number of samples is 60 and has been selected from Tehran, which has been repeated twice. After the preparation of sample, by using GC-MS, each PAEs concentration was assessed. SPSS software was used for data analysis (Kruskal-Wallis and Kolmogorov–Smirnov tests).
Results: The outcomes of this study indicated the mean of total phthalates and DEHP in all samples was 5.26 (ranged from 2.94-8.39) and 0.97 (ranged from nd-2.05) µg/L, which were lower than the existing standards (DEHP standard in water is equal to 6 µg/L).
Conclusion: According to the current results and with regard to the lower concentration of each PAEs compared with the standard levels in different types of Iranian consumed milk, it can be concluded that there is no hazardous effect for consumers.