#-18-10 4851903 0054865 2 7366-87 H-18-60 ISO 7366 INTERNATIONAL STANDARD First edition 1987-06-01 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION ME>KAYHAPOAHAAOPTAHM3ALMHO CTAHAAPTW3ALMM Animal and vegetable fats and oils - Determination of 1-monoglycerides and free glycerol contents Corps gras d'origines animale et vegetale - Dosage des mono-1 glycerides et du glycerol libre Reference number ISO 7366: 1987 (E) ovidedbyIHS No reproduction or networking permited without license from IHS 998h500 E06T58h 7366-87 h Foreword Iso (the International Organization for Standardization) is a worldwide federation of national standards bodies (isO memberbodies).The work of preparing International Standards is normally carried out through Iso technical committees. Each member body interested in a subject for which a technical committee has been established has mental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. They are approved in accordance with IsO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 7366 was prepared by Technical Committee ISO/TC 34, Agricultural food products. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. ; International Organization for Standardization, 1987 Printed in Switzerland or Standardization ovided by IHS under sewithiso No reproduction or networking permitted without license from IHS Not for Resale 298500 7366-87 EOTSt ISO 7366 : 1987 (E) INTERNATIONAL STANDARD Animal and vegetable fats and oils - Determination of 1-monoglycerides and free glycerol contents Scope 5.1 Chloroform. This International Standard specifies a method for the deter- 5.2 Acetic acid, 5 % (V/V) solution. mination of 1-monoglycerides content and of free glycerol con- tent consecutively on the same test portion. 5.3Periodic acid, 2,7 g/l solution. Weigh 2,7 g of periodic acid (HglOg) in a 1 litre volumetric flask 2 Field of application and dissolve in 50 ml of water. Make up to the mark with glacial acetic acid and mix thoroughly. Store in the dark. It is applicable to animal and vegetable fats and oils and to interesterified products of oils, fats and fatty acids with 5.4 Potassium iodide, 150 g/l solution, not containing free glycerol. iodine or iodates. It is not applicable when the sample contains 5.5 Sodium thiosulfate, standard volumetric solution, a) in addition to 1-monoglycerides : chloroform-soluble c(Na2S203) = 0,1 mol/l. polyhydric substances with two or more adjacent hydroxyl groups; 5.6 Starch, indicator solution, 10 g/l. b) in addition to free glycerol : water-soluble polyhydric Dissolve 1 g of soluble starch in 100 ml of water by stirring and substances with two or more adjacent hydroxyl groups. heating. Add 0,1 g of salicylic acid to preserve the indicator solution and boil for 3 min. Cool to room temperature. Reference 6 Apparatus Iso 5555, Animal and vegetables fats and oils -- Sampling. Usuaf laboratory equipment and in particular 4Principle 6.1 Conical flasks, of capacity 500 ml, with ground-glass stoppers. Dissolution of a test portion in chloroform. Extraction of free glycerol from this solution with acetic acid solution. Oxidation 6.2 Magnetic stirrer. of1-monoglyceridesinthechloroformsolutionbyanexcessof periodic acid solution. Addition of potassium iodide and titra- tion of the liberated iodine with a sodium thiosulfate standard volumetric solution. Sampling 7 Oxidation of free glycerol in the aqueous solution by an excess See ISO 5555. of periodic acid solution. Addition of potassium iodide and titration of the liberated jodine with a sodium thiosulf