الفهرس 
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Abstract
It is well known that polymeric food packaging materials are not completely inert and may migrate to the foods they come in contact with. Therefore, because of health and sanitation reasons, there are regulations that require the polymeric packaging materials to demonstrate a certain level of inertness towards the food are of outmost important. The quality control of food packaging materials involves the determination of migration of their constituents into foodstuffs or into food. The chemicals which are relevant are residual monomers. Technological additives and various degradation products arising during processing or storage, for the safety assessment of plastic packaging materials. There is a need for methods which allow determination of the migration of complex mixture of substances whose toxic behaviour are additive. Most commercial plastics are made in different formulations, the amount of the different additive present in anyone formulation can vary greatly, for example polyvinyl chloride could contain plasticizer, stabilizer, pigment.. etc. Plasticized polyvinyl chloride is in contact with the surrounding medium, and the plasticizer may stay in place or it may migrate to the ::tv. sUITounding medium. The other phenomena, scalping and off odours consist of losses of food constituents which have only organoleptic consequences. PolYVinyl chloride is not only the resin to which a plasticizer may be added. The widespread use of plastic materials has been accompanied by a rapid increase in the use of phthalate esters as plasticizers. In particular, the ester Di (2-ethyl hexyl phthalate). However, recent reports have described toxic and teratogenic effects of phthalate esters and too phthalates have an 86 percent share of world plasticizer market. This study to investigated the presence residue level of plasticizers Di (2-ethyl hexyl) phthalate in some food (oil-cheese-milk-water-milk-vinegar fool-coca cola) obtained from Alexandria market. All were packed in different types of plastics packaging materials (polYVinyl chloride polyethylene - polyethylene terephthalate under different storage condition, similarly the iodine value, acid value and peroxide value were determined as indicator of changes in the quality of packed food sample. Organoleptic analysis were also carried out to assess the effect of plasticizer Di (2-ethyl hexyl) phthalate on quality of packed food on materials. Migration tests are not usually carried out on food as it is analytically difficult to separate, and measure law concentration (ppm or below) of additive, therefore, specific solvents are used generally as food stimulant, the main problem lies in determining the additives in fat and oils, as many of them are only tolerated in food at levels 10,50 ppb (parts per billion) detecting additives in such small amounts in fats is very often only possible by using radioactive labeled additive (commonly carbon, carbon 14). In some countries that problem has been solved by recommending certain as fat stimulants, ex n-heptan, n.hexan. A sensitive and simple method was used in our study for the quantitative determination of migration level of plasticizers (Di (2-ethyl hexyl) phthalate. In extraction fast method was used where extraction of plasticizers Di (2-ethyl hexyl) phthalate by one step by using n-hexane found to be and effective solvent and the addition of acetonitrite optimized the extraction of Di (2-ethyl hexyl) phthalate. Gas chromatographic analysis was used to determined the level of plasticizer Di (2-ethyl hexyl) phthalate residue in packaged food. Results showed that no residue could be detected in food (oils - water - vinegar - butter - milk) which were packed in polyvinyl cWoride, polyethylene terephthalate. This is a very important finding as it showed that there is no public health hazard nom the used of this particular plasticizer in food packaging. In the case of the cheese sample the method described has been developed by taking into account the different variables which can affect the extraction process such as solvent (n hexane) used as extraction agent, the sample size where the sample cut into small pieces (6 gram) and not ground the sample of fat content. Results showed that no residue of plasticizer (Di (2-ethyl hexyl) phthalate could be detected in cheese food samples which was packedd in three different types of films (polyvinyl cWoride, polyethylene, polyethylene terephthalate. Chemical analysis, acid value, peroxide value, iodine number of (oil butter) samples were determined at different storage time where oils and water stored at room temperature for six months at each month intervals sample were removed for chemical analysis, samples of butter were cut and packed for six week, at each 2 week sample of butter were taken to chemical analysis. The result showed that the acidity and peroxide value of oil and butter increased by storage time, but iodine number decrease by time. Another important problem is the organoleptic properties of plastic for food contact, organoleptic evaluation provide useful tools in solving problems of transport and migration of off flavour into foods. ~j. Organoleptic properties were detennined for food samples (cheese, butter, water, oils) after different storage time. Water and oils after six month butter after 6 weeks, cheese after 3 days. Result indicated that polyethyleneterphtalate have high scores of acceptability for water, cheese, and oil but in butter samples, polyethylene have high scores of acceptability. From this study we can recommended that: The plastics must be produced by good manufacturing, not transfer their constituent in food stuffs in such quantities as to constitute of health hazard and too plastics must not transfer constituents to food stuffs in such quantities as to alter organoleptic properties. If plasticizer had to be added to palstics industry, it should be involatiles, permanent. It should neither change physically or chemically,. Other consideration may be non toxicity, in the end more studies on the additive which added to plastics are needed.