ISO 23349:2020 pdf downloadAnimal and vegetable fats and oils Determination of sterols and stanols in foods and dietary supplements containing added phytosterols.
Plant sterols and plant stanols, collectively referred to as phytosterols, are increasingly recognized for their role in reducing the risk of coronary heart disease by lowering serum total and low-density lipoprotein cholesterol. Because of these potential health benefits, health claim regulations authorizing the addition of phytosterols and phytosterol esters to foods and dietary supplements now exist in countries throughout Europe, North and South America, Asia, New Zealand and Australia.
ISO 23349 was developed in response to the worldwide demand for a reference method for quantifying total and individual phytosterols in foods and dietary supplements containing added phytosterols, and in the phytosterol food additive concentrates used to prepare such products. This reference method is based on the single-laboratory validated methods of Clement et al.L1i and Srigley and Haile[21 for the preparation and gas chromatographic separation of phytosterol trimethylsilyl ether derivatives, respectively.
In 2016 to 2017, an international collaborative study co-organized by the United States Food and Drug Administration (FDA), Cargill (USA) and the American Oil Chemists’ Society (AOCS) was carried out to evaluate the performance of this method for the determination of total and individual phytosterols in foods, dietary supplements and phytosterol concentrates.[] A total of 14 laboratories from 6 countries successfully completed the analysis of 18 test materials, upon which the method was approved as AOCS Official Method Ce 12-16.
This reference method is appropriate for the determination of the five major phytosterols (i.e. campesterol, campestanol, stigmasterol, 13-sitosterol and sitostanol) that are the subject of FDA’s health claim regulation for phytosterols and the reduced risk of coronary heart disease.
ISO 23349 specifies a reference method for the determination of free sterols/stanols and steryl/ stanol esters (0,1 % to 97 % mass fraction) in foods and dietary supplements containing added phytosterols and in phytosterol food additive concentrates.
Milk and milk products (or fat coming from milk and milk products) are excluded from the scope of this document. This method does not apply to matrices that contain rice bran oil at concentrations of more than 20 % due to possible interferences in the gas chromatograrn.
6.4 Capillary column, with a stationary phase that has been successfully employed to perform the separation of phytosterol TMS ethers.
The use of a bonded (5 %-phenyl)-methylpolysiloxane stationary phase column, such as the HP-5, of length 30 m, internal diameter 0,32 mm and film thickness 0,25 urn, is recommended. The use of a non-bonded (5 %-phenyl)(1 %-vinyl)-methylpolysiloxane stationary phase column, such as the SE-54, of length 30 m, internal diameter 0,32 mm and film thickness 0,25 tim, is also appropriate.
6.5 Injection port split liner, tapered, deactivated, of length 78,5 mm, internal diameter 4 mm and outer diameter 6,3 mm, with glass wool.
6.6 Microsyringe, of capacity 10 iii, with hardened needle for gas chromatography.
6.7 Sample preparation system, suitable for performing saponification and acid hydrolysis procedures, and equipped with the following.ISO-23349-2020