AOAC is exploring opportunities for characterization of whey protein hydrolysates, which are used as ingredients in various products, including infant formula, sports nutrition supplements, and medical foods—nearly a $5 billion market in 2023. Analytical solutions are needed to address method gaps.
“In the absence of global standards for whey protein characterization, different approaches and methods are used, leading to varying results,” says Seamus O’Mahony, University of Cork.
Introduced during the Analytical Solutions Forum (ASF) at the AOAC Midyear Meeting in March 2024, whey protein hydrolysates are products obtained by chemical or enzymatic hydrolysis of whey proteins. During hydrolysis, proteins are broken down into peptides of different sizes and free amino acids.
The main whey proteins are β-lactoglobulin, α-lactalbumin, bovine serum albumin, immunoglobulins, and lactoferrin. From a nutritional perspective, whey protein hydrolysates can promote muscle growth, improve antioxidant defense, and reduce inflammation, among other health benefits.
Since the AOAC Midyear Meeting, AOAC held an informative and well-attended webinar on April 17, 2024, to continue examining characterization of whey protein hydrolysates and propose a pathway forward for AOAC standards development leading to greater global harmonization. Experts provided industry and regulatory perspectives on gaps in methodologies, regulatory landscape, and analytical needs and challenges.
Several analytical approaches are available for characterization of whey protein hydrolysates: degree of hydrolysis (DH), peptide and amino acid profile, total and soluble nitrogen, molecular weight, and osmolality. DH is defined as the number of peptide bonds in a protein, which have been cleaved during hydrolysis, expressed as a percentage of the total number of peptide bonds in the intact protein. Several methods are commonly used to measure DH.
Methods for protein, peptide, and amino acid profiling include size exclusion chromatography, reverse phase chromatography, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and capillary electrophoresis.
While methods are available for the various analytical approaches for characterization, there are limitations and no standard methods.
Some challenges with analysis of whey protein hydrolysates are use of various methods that lead to different results, lack of international harmonization, equivalency testing in de-risking supply chains, requirements for nutritional product registration, and the evolving regulatory landscape. These challenges impact manufacturers, end-users, customers and consumers, regulatory agencies, and analytical laboratories.
From an industry perspective, Aine Halihan, Carbery, and Michael Affolter, Nestlé, agree that lack of harmonized, globally accepted methods is one of the biggest obstacles. Standardization is needed because methods vary and so do results. They also noted the lack of independent testing labs available. AOAC standards and methods are needed to meet customer and regulatory requirements.
Michael Barry, MjBConsulting, reported that discussions on whey protein hydrolysates characterization initiated during revision of the Codex Standard for follow-on formula. These discussions posed the question, what is meant by hydrolyzed formula?
Barry looked at the regulatory landscape in the European Union [European Food Safety Authority (EFSA) and European Commission (EU)] and China. The EFSA guidance on characterizing protein hydrolysates outlines that evaluation of infant formula and follow-on formula manufactured from protein hydrolysates should include protein source(s) of the hydrolyzed protein, identification of individual intact proteins by their molecular weight, and DH of the protein, among other information. Commission Delegated Regulation (EU) 2016/127 states that “Infant formula manufactured from protein hydrolysates shall comply with the protein-related requirements provided.”
In China, hydrolyzed formula can be regular infant formula or infant formula for special medical purposes. Indicators for assessing hydrolysates are DH, pH value, molecular weight distribution, and types, sources, and donors of enzymes used.
Use of hydrolyzed whey proteins is subject to regulatory approval, which is subject to scientific characterization of the hydrolysate. There is a need for standardization. Until then, food business operators must provide scientific characterization of hydrolysis without agreed methods of analysis.
To launch standards development activities for characterization of whey protein hydrolysates against which candidate methods can be evaluated, with the ultimate goal of Codex adoption, AOAC is seeking advisory panel members to define priorities. If you are interested in supporting this work and guiding the project’s scope, complete the interest form.
AOAC will also be seeking volunteer subject matter experts to serve on a working group to be formed to develop AOAC Standard Method Performance Requirements (SMPRs®) based on priorities established by the advisory panel. In working toward consensus, the working group will examine issues and needs, analytical challenges, technical and regulatory requirements, gaps in existing methodologies, and more. If you are interested in participating to help ensure the best available science drives public health policy and regulation, complete the form to join the mailing list.
For more information on AOAC activities for characterization of whey protein hydrolysates, contact scienceprograms@aoac.org. To view the prospectus, visit the Whey Protein Hydrolysate Rationale page on the AOAC website.
