Feed grade ingredients, feed grade meat meal ingredients for example, do not need to be transported or warehoused under refrigeration. The lack of refrigeration requirement is a selling point to pet food manufacturers, providing significant savings in labor costs. But, at the same time the lack of cooling can be an issue of concern.
An issue of concern is rancidity. “Rancidity is a common problem with processed animal products. This can have an adverse effect on both product quality and safety. It is caused by the oxidation of fats and oils, which leads to the formation of harmful compounds such as free radicals and hydroperoxides..”
Rancid pet food ingredients have short- and long-term health effects on pets. From the Eurofins laboratory: “Fierce products can cause upset stomach leading to nausea, vomiting, or diarrhea. Longer term, free radicals are a concern. Free radicals, in layperson’s terms, are atoms with unpaired electrons. These atoms are looking for electrons to pair with and often damage vital parts of our bodies and our pets such as proteins, DNA, cells, etc. In human studies, free radicals and oxidative stress have been linked to certain cancers, neurological diseases, and cardiovascular diseases such as heart disease..”
Because of the known risks of rancidity in commonly used pet food ingredients, testing for rancidity is important for manufacturers and ingredient suppliers. From Hanna’s laboratory instruments: “Rancidity or a weak amount of peroxide can affect any step of the pet food manufacturing process (ingredients/materials, raw product, production, finished product/packaging). As fats, oils, proteins, etc., are exposed to the elements, they undergo minor chemical reactions. These chemical reactions cause the oils and fats to oxidize. It affects the smell, taste, texture, and aesthetic of the finished products. Inhaling the smell of pet food can be a little off-putting – but does the food smell stale or just a little off? It is possible that rancidity has already begun. The more processed the pet food, the higher the risk for rancidity. For example, if the food is subjected to high temperatures during processing, the increased temperature can accelerate the rate of oxidation of the food..”
The pet food industry – including ingredient suppliers – conducts peroxide value testing on ingredients to check for rancidity. “The peroxide value when tested usually gives you results on the amount of oxidation per kilogram of fat/oil you are testing. In general, materials with values of 10 meq or less are considered fresh and good for use. Anything above 30 meq, the product is generally considered rancid.”
But…the industry also tells us that rancidity testing (peroxide value testing) is often inaccurate. From PetFoodProcessing.net (bold added): “Few discussions of analytical methods generate as passionate debates as the peroxide value (PV) test. It’s a passion shared by many industry experts. The best way to measure early markers of oxidation is a hotly debated topic. Today, each industry applies its preferred method to measure PVs. Unfortunately, most of these different methods often produce different results. Some of these differences are small, while others can be large. This can result in conflicts between a pet food customer and an ingredient supplier. It hurts commercial relationships and costs the industry a lot of money.”
Because of the acknowledged variability in test results for rancidity, industry representatives are working together to develop a new method for testing for rancidity (peroxide level). Among those working to develop a new method to test for rancidity are representatives from Mars Petcare, Kemin Industries (ingredient supplier), Darling Ingredients (ingredient supplier), Cargil (ingredient supplier and manufacturer), and Tyson (ingredient supplier).
The question is…should the industry be responsible for developing their own laboratory testing methods when test results play a major role in animal health and their profits? Industry acknowledges current testing variations”cost the industry a great deal of money”. Could they develop a test method that deliberately measures higher levels of rancidity (peroxide values) as lower, allowing them to use lower quality ingredients?
Or is everyone better protected if a new laboratory test method is developed ONLY by non-industrial/independent scientists (whose livelihoods do not depend on the outcome)?
Personal opinion: Because of the importance of this particular test method, independent parties must be fully involved.
We sent the FDA the following message:
The Center for Veterinary Medicine should be aware that members of the pet food industry have reported significant variations in testing methods for peroxide values of pet food/animal ingredients. By industry”Some of these differences are small, while others can be large.” Source: https://www.petfoodprocessing.net/articles/18722-inching-closer-toward-peroxide-value-measurement-standards
The industry has taken it upon themselves to develop another way to value peroxide, along with pet food manufacturing representatives and ingredient suppliers. We are concerned about the consequences of this industry-developed procedure and suggest that FDA develop a proposed agency procedure that all industry will follow.
Pet owners deserve proper and consistent testing procedures for the quality and safety of pet food ingredients. Unfortunately, we cannot trust that an industry-developed method is in the best interest of pets, so we are asking the Center for Veterinary Medicine to involve themselves in this issue immediately.
If we learn more from the FDA, it will be shared.
Wishing you and your pet(s) the best,
Susan Thixton
Pet Food Safety Advocate
Buyer Beware of Author, Co-Author Dinner PAWsible
TruthaboutPetFood.com
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