Study of Management of used edible oils and peroxid level in food production and distribution centers of Tabriz

Abstract

Introduction: Oxidation of lipids is the main cause of their corruption, and hydro peroxides formed from the reaction between oxygen and unsaturated fatty acids are primary products of this reaction, which are harmful to health and human nutrition. The amount of change and destruction, to a large extent is influenced by the nature of fried oil and causes of frying. In order to reduce environmental pollution, consumed oils wastes can be used in making biofuels. Materials and methods: This is descriptive - cross sectional study conducted in the city of Tabriz on seven guilds of confectionery, fast food and sandwich sellers, telephone food shopping, baklava cooking, self-service restaurant, hospital centers kitchen and strudel pastry in 97 food supply and distribution center with 375 random samples. The peroxide in Food and Drug reference lab, the percentage of polar compounds and temperature of frying oils in the place were determined with TESTO 270 made in Germany. The necessary information such as duration of using oil per day up to waste time was specified in a questionnaire and also the frequency of using oil per day was recorded. The collected data were analyzed with SPSS software and descriptive indicators. Findings: Results of this study showed that amount of peroxide in confectionery guild for 28.9% of samples were unusable and the highest peroxide value was 19.1 meq/kg oil, 80.5% of samples were unusable and the highest peroxide value was 77.9 meq/kg oil in fast food and sandwich sellers guild, 40.7% of samples were unusable and the highest peroxide value was 50 meq/kg oil in telephone food guild, 33.3% of samples were unusable and the highest peroxide value was 23.2 meq/kg oil in baklava cooking guild, 80% of samples were unusable and the highest peroxide value was 21.7 meq/kg oil in restaurant guild, 33.3% of samples were unusable and the highest peroxide value was 11.3 meq/kg oil in central kitchen of hospital guild, and 37.5% of samples were unusable and the highest peroxide value was 8.03 meq/kg oil in strudel pastry guild. Results of this study showed that the percentage of polar compounds in confectionery guild for 28.9% of samples were unusable and the highest amount of polar compounds in frying oils was 52 percent,b 79.9% of samples were unusable and the highest amount of polar compounds in frying oils was 97.5 percent in fast food and sandwich sellers guild, 44.4% of samples were unusable and the highest amount of polar compounds in frying oils was 80 percent in telephone food guild, 37% of samples were unusable and the highest amount of polar compounds in frying oils was 63 percent in baklava cooking guild, 83.3% of samples were unusable and the highest amount of polar compounds in frying oils was 57 percent in restaurant guild, 37.5% of samples were unusable and the highest amount of polar compounds in frying oils was 34 percent in central kitchen of hospital guild, and 41.7% of samples were unusable and the highest amount of polar compounds in frying oils was 29 percent in strudel pastry guild. Based on statistical analysis of Mann - Whitney in terms of peroxide and the percentage of total polar compounds for seven guilds, there was statistically significant difference between the two groups with the ability to use and non-use of consumed oils (Pvalue ≤ 0.001). Validity of instruments and methodology with three repetitions were surveyed by statistical tests of Repeated Measures between different periods and modes of sampling in all of food supply and distribution centers and in seven guilds. With the proximity of results of peroxide numbers and percentage of total polar compounds in frying oils exception of two cases,, validity of instruments and methods of working were proved between different periods and scenarios of sampling (Pvalue < 0.05). Checking the results about the way of disposal of frying oil showed the most methods used were respectively collection by unknown persons, disposal with municipal waste, pouring in municipal sewage networks, re-using, pouring in surface water channels and pouring in absorbent wells. Discussion: The findings showed that the peroxide and the percentage of total polar compounds of consumed oils in confectioneries, fast food and sandwich sellers, telephone food, baklava cooking, self-services and restaurants, central kitchen of hospitals, and strudel pastry were higher than the standard level. Test results of Spearman correlation method between measured variables in all centers showed that there is a high correlation between variables measured. The findings of this study are consistent with results of other colleagues in the field a lot. The resultsc showed that current disposal methods Waste of edible oils are inappropriate, and study results in the world showed that the production of biodiesel from wastes of edible oil is one of the best alternative in produced waste management. Conclusion: The findings showed that the use of oils used in the study guilds was unfavorable and various factors are effective in this respect. Waste disposal of frying oil is improper. To improve the situation, more training, organizing and monitoring are needed in this area.