Challenge to evaluate regulatory compliance for nutrients in infant formulas with current state-of-the-art analytical reference methods

Abstract

Infant formulas are strictly regulated and rigorously tested for compliance. Recently, new official analytical methods/standards have been established for nutrient analyses in these product categories through the Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN), governed by AOAC INTERNATIONAL. Many of these methods have been adopted or are in the process of being adopted as reference methods by Codex Alimentarius. The purpose of this paper is to assess the ability of these cutting-edge analytical methods to deliver acceptable results in the context of established regulatory limits for nutrients in food standards and regulations. For this evaluation, the analytical method variability is considered as one of the three main sources of overall process variability, which also includes variation in raw materials/ingredients and the manufacturing process.The process capability (Cp) is a concept for determining the overall process variability relative to specification limits for a parameter in the final product. Based on this principle an analytical method capability (Cm) was defined and calculated for SPIFAN methods. Global regulatory requirements were evaluated including minimum and maximum limits and tolerances from the declared label values. Compared to these requirements, analytical methods for vitamins A, B12, D and folic acid are of particular concern in relation to the requirements in China, some EU member states, Pakistan, Russia, Singapore, South Africa and Thailand. For a product with a manufacturing target at the midpoint of the regulatory range for these nutrients, the probability of obtaining an analytical result outside the regulatory requirements due to analytical variation alone can be as high as 19%. This does not consider variability caused by the production process and/or raw materials/ingredients.These currently used analytical methods are state-of-the-art and represent the latest developments in technology. However, this work demonstrates that continuous method improvements for the nutrients identified must be pursued. In addition, this work supports a risk management approach that takes into consideration analytical method capability when establishing regulatory limits for nutrients in infant formulas. Ongoing efforts towards harmonization of regulatory requirements across global markets will facilitate evaluation of regulatory compliance in infant formulas.