Determination of iodine value of fats and oil discover food. Hence the iodine number of the oil is 260x45 results and discussion the iodine number is an important characteristic of oils as it. The iodine value is a measure of the unsaturation of fats and oils and is expressed in terms of the number of centigrams of iodine absorbed per gram of sample. Does hydrogenation affect the nutritional value of vegetable oils. Iodine value is a useful parameter in studying oxidative rancidity of oils since higher the unsaturation the greater the possibility of the oils to go rancid. The iodine value or iodine adsorption value or iodine number or iodine index, commonly abbreviated as iv in chemistry is the mass of iodine in grams that is consumed by 100 grams of a chemical substance. It is expressed as the number of grams of iodine that will react with. Determination of iodine value of oil lipids laboratory methodology. Jan, 2017 a general iv model that incorporates several oil types is expected to improve prediction performances. Iodine value determination of edible oils using atr. Iodine value iv, typically determined by the wijs method, is a measure of the degree of unsaturation or double bonds in fats and oils and is expressed in terms of the amount of iodine g reacted per 100 g of sample. Astm d555415 standard test method for determination of the.
Astm d5768 022018 standard test method for determination. This article is published and distributed under the terms of the oxford. Determination of physicochemical constants of fats and oils. Determination of iodine value of palm oil by differential.
Determination of iodine value of oil the iodine value is a measure of the degree of unsaturation in an oil. The more iodine is attached, the higher is the iodine value, and the more reactive, less stable, softer, and more susceptible to oxidation and rancidification is the oil, fat, or wax. The aim of the present paper was to work out such a procedure and chart which, based on a single gasliquid chromatogram of a fatty acid mixture, would. The mean value of the blank determination method 051b is automatically stored as auxiliary value h3. Jun 19, 2020 iodine value means the g value of halogen which adhere to g of methods such as hanus method and wijs method for iodine value.
Sep 10, 2020 iodine value means the g value of halogen which adhere to g of methods such as hanus method and wijs method for iodine value. This document specifies a reference method for the determination of the iodine value commonly known in the industry as iv of animal and vegetable fats and oils, hereinafter referred to as fats. Pipette out 10ml of fat sample dissolved in chloroform to an iodination flask labeled as test. It is expressed as the number of grams of iodine that will react with the double bonds in 100 grams of fats or oils the determination is conducted by dissolving a weighed sample in a nonpolar solvent such as cyclohexane, then adding glacial acetic acid. Standard test method for determination of the iodine value. As early as 1854 knop proposed the use of potassium bromate and hyclrobromic acid for the determination of iodine values and lately again tolle j. It is expressed as the number of grams of iodine that will react with the double bonds in 100 grams of fats or oils. Iodine value of edible oils and fats according to wijs. Therefore, it is hypothesized that the iv of an oil can be determined based upon the tg composition of the oil. Determination of physicochemical constants of fats and. Pdf standard test method for determination of the iodine.
Iv is a measure of the number of double bonds in the unsaturated fatty acids in one gram of oil. Since 450 mg of the oil takes up 26x mg of iodine 1 mg of the oil will take up 26x450 mg of iodine and 100 mg of the oil will take up 260x45 mg of iodine. Iodine value wijs method pdf new pdf download service. The oil itself is semisolid and reddishorange in color owing to the presence of carotene provitamin a. Determination of iodine value of oil lipids laboratory. Ftir method combined with interval optimization is described to determine the iodine value in edible oil. The iodine value of a substance is the weight of halogens expressed as iodine absorbed by 100 parts by weight of the substance. Determination of the iodine value of oils and fats. When oil is treated with excess of wijs solution i. Moisture content of oils and fats is the loss in mass of the sample on heating. In fatty acids, unsaturation occurs mainly as double bonds which are very reactive towards. Determination of quality parameters of crude palm oil using. Determination of the iodine value of oils and fats results of. Pdf the content of unsaturated fatty acids in different lipids.
Iodine value of sunflower oil the determination of iodine value is of great importance in finding the proportion of adulteration in oils this gives an idea of its drying character. The commission on oils, fats and derivatives of the iupac, x. Standard methods for the analysis of oils, fats and derivatives. Iodine numbers are often used to determine the amount of unsaturation in fats, oils and waxes. Unsaturated oils and fats become rancid by oxidation, forming peroxides. Determination of acid value acidity, of iodine value, and of peroxide value. In our experience, it is an important and easily available parameter in fat selection. The quantity of substance used in the determination should be such that at least 70% of the iodine added, as provided in the recommended procedure, is not absorbed. Standard test method for determination of the iodine value of. This method describes the determination of peroxide values for animal oils and fats, vegetable oils and fats, as well as for flavour and fragrance materials. Iodine value of edible oils and fats according to wijs aoac. Determination of quality parameters of crude palm oil. Final determination regarding partially hydrogenated oils. Iodine value the iodine value of an oil fat is the number of grams of iodine absorbed by 100g of the oil fat, when determined by using wijs.
Animal and vegetable fats and oils determination of iodine value. The oil fat sample taken in carbontetrachloride is treated with a known excess of iodine monochloride solution in glacial acetic wijs solution. The processors of oil and fat are in need of a quick determination method of iodine value of oils and fats especially in case of checking the degree of. Therefore, the present method represents a rapid and accurate tool for measuring iv of edible fats and oils. Jan 18, 2019 iodine value means the g value of halogen which adhere to g of methods such as hanus method and wijs method for iodine value. Estimation of iodine value of fats and oils procedure. Test method for measurement of iodine value of fats and oils stipulated in the below quoted standards is. Astm d5554 15 standard test method for determination of the. The determination is conducted by dissolving a weighed sample in a nonpolar. Iodine value iv is used as a parameter in process control as well as a quality parameter in traded palm oil products.
Determination of iodine and saponification values of silver. Therefore, the thermal behavior of an oil could reflect its iodine value. A simple and practical method for determining iodine values of oils. Fats and oils are a mixture of triglycerides which are. Oct 26, 20 determination of iodine value definition. Standard test method for determination of iodine value of tall oil fatty acids. Calculation of iodine value from measurements of fatty acid methyl. Iodine value means the g value of halogen which adhere to g of methods such as hanus method and wijs method for iodine value. All abovementioned charts could be used only for the determination of single constants and mostly only for the determination of the iodine value. Saponification value or saponification number, also referred to as sap in short, represents the number of milligrams of potassium hydroxide or sodium hydroxide required to saponify 1g of fat under the conditions specified. Iv measures the number of double bonds in the molecular structure of an oil. The peroxide value is a parameter specifying the content of oxygen as peroxide, especially hydroperoxides in a substance. Then the flask is allowed to stand for a half an hour incubation in dark. When this is added to a solution to be tested, however, any chemical group usually in this test cc double bonds that react with iodine effectively reduce the strength, or magnitude of the color by taking i 2 out of solution.
The present work describes a novel procedure for determination of iodine value based. Various parameters are used to assess its quality, including iodine value iv, moisture and free fatty acid ffa content. Calculation of iodine value from measurements of fatty acid. Pdf determination of iodine value in triisocetyl citrate. For groundnut oil, the iodine values were found to be 86. Parameters of crude palm oil using nearinfrared spectroscopy. To form a double bond, carbon requires more energy 615 kjmol than to form a single bond 350 kjmol. Determination of iodine value iv in fats and oils with thermometric. Aug 21, 2019 en iso 3961 animal and vegetable fats and oils determination of iodine value astm d5554 standard test method for determination of the iodine value of fats and oils aoac 920. Iodine value refers to the percentage of iodine absorbed by a substance such as a fat or. Society aocs cd 125 describes the determination of the iodine value a measure. This document specifies a reference method for the determination of the iodine value commonly known in the industry as iv of animal and.
Add 20ml of iodine monochloride reagent in to the flask. Determination of iodine value of palm oil based on. The iodine value is in direct proportion to the number of mono and polyunsaturated bonds within the constituent fatty acids. The values given in parentheses are for information only. The used method was based on determination of iodine number by titration with sodium thiosulfate. A new calculation method for the determination of iodine value iv from measurements of fatty acid methyl esters is proposed. The determination of iodine value is a particular example of iodometry.
Pdf unsaturated fatty acids play an important role in human diet and. Astm d555415 standard test method for determination of. Determination of iodine and saponification values of. Determination of iodine value pharma qualification. Standard methods for the analysis of 1st supplement to the. The determination of the iodine values of fats and oils by.
In performing the test, a known excess of iodine, usually in the form of iodine monochloride, is allowed to react with a known weight of the oil, fat, or wax, and. Standard methods for the analysis of oils, fats and. Purchase your copy of astm d5768 022018 as a pdf download or hard. No other units of measurement are included in this standard. Annex a describes a method for the calculation of the iv from fatty acid compositional data. The iodine number stands for the amount of iodine that can be bound by addition by some fat oil or fatty acid. The analytical methodology of its evaluation includes the use of. Rapid method for determination of iodine numbers of vegetable oils. May, 2020 iodine value means the g value of halogen which adhere to g of methods such as hanus method and wijs method for iodine value.
Calculation of iodine value from measurements of fatty. The results obtained when using carbon tetrachloride were compared to those obtained when using a substitute solvent mixture of cyclohexane and glacial acetic acid. Determination of saponification and iodine value of sunflower oil. A b s t r a c t the iodine value iv also called iodine number or iodine absorption value is an important analytical characteristic of unsaturation of fats and oils. The iodine value is a measure of the degree of unsaturation in an oil. The method is based on the quantitative determination of fatty acid methyl esters of vegetable oils by capillary gas chromatography. A rapid and practical method for determining the iodine value iv of edible oils or fats with an ftir spectrometer combined with a quartz cuvette was reported. Crude palm oil cpo is obtained from the fibrous mesocarp reddish pulp of palm fruit. The vegetable oils were analyzed for their iodine values and the following results were obtained. Determination of saponification and iodine value of.
The iodine value for native oils fats of defined plant origin is easily accessible from tables or from the fat supplier table 3. Fast spectrophotometric determination of iodine value in biodiesel. Jan 14, 2020 two collaborative studies were conducted using the wijs method for determining the iodine value in a wide range of vegetable and animal oils and fats. Iodine value, also called iodine number, in analytical chemistry, measure of the degree of unsaturation of an oil, fat, or wax. Iodine value iv is a measure of the total number of double bonds present in fats and oils. To determine the iodine value of sunflower oil, palm oil and corn oil by cyclohexane method. Determination of iodine value iv in fats and oils metrohm. Determination of peroxide value pov in fats and oils. Iodine value is a measure of unsaturation of oils and fats. The peroxide value is a measure of the oxidation present. The iodine value is a measure of the unsaturation 3. Standard test method for determination of the iodine value of fats and oils. Pdf iodine value in partially hydrogenated castor oil ricinus oil. Annex b describes a method for the calculation of the iv from fatty acid compositional data.
Estimation of iodine value of fats and oils amrita. Determination of iodine value presented by harish pudi m pharm, 2nd sem dept of pharma analysis, pes college of pharmacy. The iodine value can be determined for fats and oils with thermometric titration, by dissolving a weighed sample in a nonpolar solvent and then. To retard rancidity keep oils and fats in cool place and protect from light and air.
Unused icl reacts with ki solution and liberates an equivalent amount of iodine, which is titrated against standard sodium thiosulphate solution. The iodine value of an oil fat is the number of grams of iodine absorbed by 100g of the oil fat, when determined by using wijs solution. The determination of the poz is done by titration with sodium thiosulfate after reaction of the sample with potassium iodide, wherein the iodide is oxidized by the peroxides to iodine. Mar 21, 2020 iodine value means the g value of halogen which adhere to g of methods such as hanus method and wijs method for iodine value. We have an intake of 50 students per year who, for practical exercises, are divided into two batches of 25.
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