[Effects of salep, glycerol and sunflower oil on potato starch-based edible film]

Starch is one of the most abundant carbohydrate biopolymers with excellent film-forming properties. However, it has a poor resistance to water vapour and poor mechanical properties. The objective of this studt was to determine the effects of glycerol, oil and salep on the film properties of starch. Edible films based on mixtures of starch and salep [an Iranian gum] were prepared and their properties [mechanical and optical charactersitics, solubility, and water vapor permeability [WVP]] investigated. The mixtures were as follows: potato starch and salep [1-5%], potato and glycerol plasticizer [10-40%], and potato and sunflower oil [0-20%]. The results showed that the physical and mechanical properties of potato starch-based edible films were affected by the their contents of salep, glycerol, and sunflower oil. The salep gum increased tensile strength, elastic modulus, and C[asterisk], but reduced elongation at break and L[asterisk], while glycerol reduced tensile strength, elastic modulus, and UV transparency but increased elongation at break, L[asterisk], opacity, solubility and WVP. On the other hand, sunflower oil decreased elongation at break, tensile strength, elastic modulus, UV transparency, solubility, and water vapor permeability, but it increased opacity. Based on the findfings, it can be concluded that the optimum contents of salep, glycerol, and sunflower oil in potato starch-based edible films are 3%, 32%, and 8%, respectively

Influence of heating on antiradical activity of essential oils of thyme, summer savory and clove by 2, 2- diphenyl-1- picrylhydrazyl [DPPH] method

Great interest has recently been focused on the addition of herbs and their derivatives to foods and biological systems, due to their well-known abilities to scavenge free radicals. For this reason, the antiradical activities of essential oils of thyme [Thymus vulgaris L.], summer savory [Satureja hortensis L.] and clove [Syzygium aromaticum L.] were studied. The essential oils of these medicinal plants were analyzed by GC/MS and the major chemical components were identified. Also, antiradical activities of these essential oils were evaluated by using DPPH radical. Samples were kept at 120 and 180°C for 0.5, 1, 2, and 3 hours to evaluate the influence of heating on the essential oils, then compared with controls [essential oils before heat treatment]. Results showed that clove oil had the highest antiradical activity and followed by summer savory and thyme oil, respectively. The essential oils showed various behaviors under different treatments of heating. All tested essential oils had radical scavenging activities at room temperature. These essential oils showed various behaviors under different heat treatments which it may be due to their different compositions

evaluation of common visual disorders in primary school children in Fasa City

Population based data concerning the prevalence of visual impairment in children are not readily available in Iran. The purpose of this study was to estimate the prevalence of common visual disorders [ambtyopia, strabismus and refractive errors] in a group of primary school children and to compare the findings with similar studies. Ten percent of the primary school children in Fasa were selected by systematic random method. They enrolled into prospective vision screening program combining the identification arm [screening] and diagnostic/treatment arm [ophthalmic examination].The screening consisted of Snellen chart presented at 6 meters test distance. An ophthalmologist in ophthalmology clinic examined each child failing the vision screening. 1224 children were screened during the 1999-2000 academic year.196 [16%] failed the vision screening [VA