Protein Verification in Pet Food: Why Testing Matters

Protein Verification in Pet Food: Testing Methods, Accuracy, and Label Compliance

Protein is one of the first things pet owners look at when choosing a food. It drives nutritional value, supports growth and muscle maintenance, and plays a major role in how pet foods are marketed and regulated. Protein is a central part of pet food formulation and marketing, and that verification has become a major focus for regulators and industry partners. Testing is the only reliable way to confirm that a formula includes the ingredients it claims and that the finished product delivers the protein levels listed on the label.

Why Is Protein Verification Testing Required?

Protein claims on pet food labels are regulated at both the federal and state levels. AAFCO model regulations and FDA requirements expect manufacturers to meet minimum nutritional standards and use truthful, well-supported statements on packaging. Any statement related to protein, whether it’s a guaranteed crude protein percentage, a descriptive name like “with beef,” or a positioning claim such as “high protein,” must be supported with verifiable data.

Accurate protein testing also helps prevent economically motivated adulteration. Because certain proteins are more costly, manufacturers need to confirm that declared ingredients are present and that no lower-quality fillers, non-protein nitrogen compounds, or undeclared species have been substituted. Verification is essential for truthful labeling, nutritional accuracy, and maintaining consumer trust in pet food products.

How Do Labs Verify Protein Levels?

Protein verification begins with quantitative testing. Laboratories rely on validated analytical methods to measure nitrogen and calculate crude protein, a standard practice across the pet food industry:

• Kjeldahl protein analysis, one of the most established methods for determining total nitrogen.
• Dumas combustion, a faster nitrogen-based method with strong repeatability and lower environmental impact.
• Amino acid profiling, which goes beyond crude protein to determine essential and non-essential amino acid levels.

Nitrogen-based methods are widely accepted as the industry standard for label compliance, while amino acid analysis helps manufacturers evaluate ingredient quality, compare protein sources, or confirm that a formula meets specific nutritional targets.

How Does Ingredient Authenticity Fit into Protein Verification?

Ingredient authenticity is an essential part of protein verification because accurate crude protein numbers alone don’t confirm that the protein comes from the correct source. As more brands use premium and species-specific ingredients like salmon, lamb, duck, venison, and other novel proteins, verifying that those ingredients are genuine has become a critical quality step. 

Laboratories use tools such as DNA species identification to confirm that the proteins match what appears on the label, along with chromatography and mass spectrometry to detect chemical markers linked to specific ingredients. Together, these methods help prevent adulteration, species substitution, and mislabeling while supporting regulatory compliance and reducing the risk of costly recalls in the pet food industry.

How Does Protein Testing Support Nutritional and Label Claims?

Manufacturers often highlight protein-related benefits on packaging, from muscle support to energy maintenance. To make these claims, companies need documentation that shows their formulas meet the nutrient profiles and ingredient standards they advertise.

• Guaranteed analysis panels reflect actual nutrient levels
• AAFCO nutritional adequacy statements are correctly supported
• “High protein,” “protein-rich,” and performance-focused claims remain accurate
• Species-specific or novel protein claims match the formula
• Marketing statements align with regulatory definitions

Testing provides the documented evidence needed for consistent labeling and helps manufacturers avoid under- or over-reporting crude protein on finished products.

Regulatory Expectations

Regulatory partners expect manufacturers to have documented programs for verifying both ingredients and finished products. This includes routine crude protein testing using validated analytical methods, along with strong supplier verification and traceability practices. Manufacturers are also expected to correctly identify and declare all animal or plant protein sources and follow AAFCO naming rules for statements such as “with,” “flavor,” and “recipe.” Meeting the requirements of state feed control officials and FDA pet food regulations is part of this process as well. Since accurate labeling and authentic ingredients remain key enforcement priorities, dependable verification practices play an important role in reducing regulatory risk and improving product consistency.

What Should Manufacturers Consider When Building a Protein Verification Program?

Protein verification works best when integrated into a proactive quality system. Manufacturers can strengthen their programs by:

• Testing raw materials before production to confirm quality and species identity
• Reviewing certificates of analysis and verifying supplier controls
• Conducting batch-level protein testing on finished products
• Using authenticity testing for high-value or novel protein ingredients
• Keeping documentation current to support labeling, nutritional claims, and audits
• Periodically reviewing formulations to make sure labels still match the product

Protein verification has become a defining part of modern pet food manufacturing, touching everything from ingredient sourcing to label accuracy and nutritional claims. As formulas grow more specialized and consumers pay closer attention to what their pets eat, consistent testing and clear documentation help ensure that products deliver the quality and transparency pet owners expect.