ISO 30024:2024

Overview

ISO 30024:2024 - Animal feeding stuffs - Determination of phytase activity - specifies a standardized, laboratory method to quantify phytase activity in animal feed and feed-related products. The method is collaboratively validated for complete and complementary compound feeds (including mineral feeds), premixtures, feed additives and plant-origin feed materials. It quantifies enzyme activity by measuring inorganic phosphate released from phytic acid (phytate) but does not distinguish added (exogenous) phytase from endogenous phytase and is not a predictive test of in vivo efficacy.

Key topics and technical requirements

• Scope and applicability: Validated for feed raw materials, compound feeds, mineral feeds, premixtures and feed additives.
• Principle of the assay: Phytase hydrolyses phytic acid (myo-inositol hexakisphosphate) releasing inorganic phosphate; released phosphate forms a yellow complex with an acidic molybdate/vanadate reagent and is read spectrophotometrically at 415 nm against a phosphate standard curve.
• Phytase unit (U): Defined as the amount of enzyme releasing 1 µmol inorganic phosphate per minute at pH 5.5 and 37 °C under the method’s reaction conditions.
• Reagents and substrate specifications: Phytic acid (or salts) used as substrate must meet purity requirements (≤ 0.1% inorganic phosphorus; assay ≥ 90% on P basis; IP6 fraction > 95%). Crystallization water for salt hydrates should be in the stoichiometric range of 10–13 mol.
• Method content: Detailed sections cover reagents, apparatus, sampling and sample preparation, extractions for different feed types, procedural steps (standards, blanks, controls), calculations (standard curve, activity calculation, corrections), precision (LOD/LOQ, repeatability, reproducibility) and test reporting. Informative annexes present interlaboratory study results.
• Safety and quality: The standard includes warnings on hazardous reagents and guidance for quality control (phytate blank OD thresholds, phytase level controls).

Practical applications and users

ISO 30024:2024 is intended for:

• Feed and ingredient quality-control laboratories performing phytase assays
• Feed additive and enzyme manufacturers for batch testing and labelling support
• Contract testing and certification bodies ensuring compliance with product specifications
• Research & development groups optimizing enzyme formulations (note: does not measure in vivo efficacy)
• Regulatory and trade laboratories verifying declared phytase activity in feed consignments

Keywords: ISO 30024:2024, phytase activity, animal feed, phytase assay, feeding stuffs, feed additives, compound feed, premixtures, phytic acid, phosphate assay.

Related standards and context

• Prepared by ISO/TC 34/SC 10 in collaboration with CEN/TC 327 under the Vienna Agreement.
• Cross-references: ISO 20588:2019 (terminology and feed definitions) and other CEN/ISO methods for feed analysis and sampling.