ISO 30024:2009, a standard method for determining phytase activity now published
In 2008, Members of the EU Feed Additives and Premixtures Association (FEFANA) Task Force on Phytase together with Gisèle Gizzi and Christophe von Holst of the European Commission’s Community Reference Laboratory (CRL) proactively cooperated in an interlaboratory study on the determination of phytase activity in feed which was eventually issued in the Journal of AOAC International (Vol. 91, No. 2, 2008). Later on, this team of experts went on with successful participation in CEN (European Committee for Standardisation) and ISO (International Organization for Standardization) activities for the development of an international standard on the determination of phytase activity in animal feeding stuffs. The standard, known as ISO 30024:2009, has reached the publication stage this summer.
For several years, an interlaboratory study has been conducted to determine performance characteristics of a new method for the determination of phytase activity in feed samples. The method, developed by FEFANA, is based on the principle that inorganic phosphate is released from the substrate phytate under defined assay conditions, and it has been validated for its suitability to measure enzyme activity of various phytase products. Two different experimental designs of the study were applied, allowing for the estimation of the precision of the method under repeatability, intermediate precision and reproducibility conditions, respectively. The results of this study were compiled, summarized and finally published in the Journal of AOAC International.
After several months of hard work by the FEFANA representatives and through proactive participation in rewriting the study according to strict CEN and ISO editing rules, the international standard ISO 30024:2009 entitled Animal feeding stuffs - Determination of phytase activity was finally published in July 2009. ISO 30024:2009, based on the study report previously issued in the Journal of AOAC International, specifies the determination of phytase activity in feed samples.
The ISO 30024:2009 method does not distinguish between phytase added as a feed additive and endogenous phytase already present in the feed materials. This standard cannot be used to evaluate or compare the in vivo efficacy of the phytase product. It is not a predictive method of the in vivo efficacy of phytases present on the market as they can develop different in vivo efficacy per unit of activity. The method is suitable and validated exclusively for the determination of phytase activity and exclusively in complete feeds.
English and French versions of this method are available in PDF format for the price of CHF 74.00 each via the official ISO web site: click here for more information.
The harmonized method which has been developed is a tool to quantify phytase products in feed samples, premixtures and for the additive per se. The method will allow the analysis of all currently EU authorized phytases in feed samples and other matrixes. The collaborative work with the CRL has undoubtedly been tremendous and crucial on this matter. FEFANA hopes that such a close cooperation will continue through other future projects.
Experts of the FEFANA Task Force on Phytase who participated in the study which led to the ISO standard are: Peter Thyregod (Novozymes), Gérard Bertin (Alltech), Kurt Vogel (DSM), Mai Faurschou- Isaksen (Danisco), Roland Betz (BASF), Richard Murphy (Alltech) and Betina Brandt Andersen (Novozymes).
