Perspective: Assuring the Quality of Protein in Infant Formula

Area of Science:

• Nutritional Biochemistry
• Food Science and Technology
• Regulatory Science

Background:

• Current infant formula regulations mandate the protein efficiency ratio (PER) rat bioassay for protein quality assessment.
• Authoritative bodies and international consensus question the PER's suitability for scoring infant formula protein quality.
• The PER's control protein, casein, does not align with the essential amino acid profile of human milk.

Approach:

• Review of current regulations and methodological recommendations for protein quality assessment in infant formula.
• Analysis of the limitations of the PER, particularly concerning its control protein (casein) and relevance to infant nutrition.
• Evaluation of the essential amino acid pattern of human milk as an international standard for infant formula protein quality.

Key Points:

• The PER bioassay may provide a false assurance of protein quality due to its reliance on casein as a control.
• The essential amino acid pattern of human milk is the internationally accepted standard for infant formula protein quality.
• Methodological adjustments to PER by the FDA focus on controlling nonprotein variables, not addressing the core issue of the control protein.

Conclusions:

• The FDA should revise protein quality assessment methods to align with the human milk essential amino acid pattern.
• Adopting the human milk standard would simplify the process, conform to international norms, and ensure accurate protein quality evaluation.
• Alternative methods for protein quality determination can be selectively employed for novel protein sources or manufacturing process evaluations.