WIJS SOLUTION FOR DETERMINATION OF IODINE VALUENo modern food production can exist and proceed without a permanent improvement in the quality of products and control of its safety. High competition, growing customer requirements, constant monitoring by government agencies and public organizations require full compliance of goods with state standards, specifications and other industry standards. Edible fats and oils are used for manufacturing a wide range of food products. Factory laboratories of confectionery, dairy, fat, oil and meat factories regularly perform a large number of various physical and chemical analyzes aimed at controlling the composition and quality of both ingredients and finished products. Iodine value is an important indicator of lipid compositionOne of the most important characteristics of lipids is their fatty acid composition which is determined by gas chromatography or wet chemistry methods. In this way, the qualitative and quantitative fatty acid composition, and the amount of trans-isomers are determined, as well as iodine value of fats and oils. Iodine value allows to judge about the degree of unsaturation of the fatty acids presenting in the fat. The higher the content of unsaturated fatty acids, the higher the value of iodine value. The main advantages of determination of iodine value using the Wijs solutionIt should be noted that determination of iodine value by the chromatographic method has several significant disadvantages. The first is a large spread of the values obtained for different devices. At the same time, the determination of iodine value using the Wijs solution (a solution of iodine monochloride ICl in an organic solvent) makes it possible to obtain accurate values regardless of the equipment used. The second disadvantage of the chromatographic method is its high cost and complexity. Besides, not many laboratories can afford to buy and operate a chromatograph. The cost of equipment for titrimetric determination is much lower, and the speed of analysis is many times faster. The third important point is that the determination of iodine value using the Wijs solution is recognized as the arbitration method. The data obtained on a chromatograph, in the case of any disputes and proceedings, cannot serve as a basis for making a decision. Since November 2018, the Wijs solution has been produced in St. Petersburg by LenReactiv JSC. The solution production time is 2-3 working days, and the minimum order quantity is 1 liter.
|