We proved the way conventional pet foods are processed adversely affects their nutritional value

The kibble wars
Written by Pure Pet FoodPure Pet Food are the experts in healthy dog food and healthy dogs featured in media outlets such as BBC, Good Housekeeping and The Telegraph. Working with high profile veterinary professionals and nutritionists, Pure Pet Food are changing dog food for the better. - Our editorial process

We have learned a big lesson recently and wanted to share it with you.

For too long now the pet food industry has forced the idea that feeding our pets a highly processed, additive-rich brown biscuit is best. Do you remember Turkey Twizzlers? Well, to us that is kibble biscuits! We created Pure Pet Food as a response to this; a highly nutritious, low processed, natural pet food with no nasties … pure in name and pure in nature. We felt so strongly that people needed to hear about this healthy way of feeding that we took our message on TV.

Simple, you think. Not quite. It turns out that getting a script approved for TV is no easy matter, especially when you’re looking to really prove how nutritious your product is against other, mainstream alternatives. And the hoops we have jumped through and the success that we have had in being able to prove and justify our claims and having the ad cleared to air on TV is a testament we thought worth sharing with you.

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Because it is proof and double proof that we are what we say we are and that the battle we set out to win to transform the diets of pets and, in turn, their health is one worth fighting. Overall this felt like a big victory for the little guy and a big step in the right direction to fulfilling our mission to change the lives of pets for the better.

Sound like something you’d like to hear more about? Then read on to see the full details of what we have sent as evidence to support our claims made on our TV ad and click here to see the ad in all its glory.

We are genuinely PURE

They said:

(i) The term “Pure” as applied to a pet food could be taken to imply that it is used as an adjective and suggest that this food is pure whereas others are not and could thus be adjudged inferior. It is hard to see how any pet food could be described as “pure”. I wonder whether this could be misleading to the purchaser?

We responded:

We decided to choose the name Pure as it describes our product. Unlike other pet food brands, we don’t use any by-products, meat meals, meat by-products, digest. See explanations below of “pet grade” ingredients –

(Source of explanations - U.S. Food and Drug Administration, Center for Veterinary Medicine (www.fda.gov/cvm), Interpreting Pet Food Labels by David A. Dzanis, DVM, Ph.D., DACVN)

“By-products (for example, chicken by-products or beef by-products): clean non-rendered "parts", other than meat, derived from slaughtered mammals. It includes, but is not limited to lungs, spleen, kidneys, brain, blood, bone, fatty tissue and stomachs and intestines freed of their contents. This is a cheap way for pet food companies to keep the protein levels "high" (although not high quality) while keeping food production costs low.

Meat Meal (for example, lamb meal): in this example, all lamb tissues, exclusive of blood, hair, hoof, horn, hide trimmings, manure, stomach and rumen contents that are cooked (rendered). After cooking, the dried solids are added as "meal" to pet food.

Meat By-product Meal (for example, chicken by-product meal): chicken by-products (defined above) that are cooked (rendered). After cooking, the dried solids can be added to pet food.

Digest: material from mammals which results from chemical breakdown of clean meat tissues or by-products ("parts" other than meat). This is often used to give a meat "flavour" to pet foods that don't contain any real meat.

Chemical preservatives: Manufacturers use chemical preservatives instead of natural preservatives as they are cheaper.

Butylated Hydroxytoluene (BHT, E321) – used within other industries such as food packaging, cosmetics, rubber products and petroleum products. The World Health Organization has named both BHT and BHA as suspicious cancer-causing compounds.

Butylated Hydroxyanisole (BHA, E320) – used in packaging materials and food containing fats and oils. The State of California has now identified BHA as a possible carcinogen (an agent directly involved in causing cancer)

We can prove we are more nutritious than ‘over-processed’ alternatives

They said:

(ii) Is conventional pet food over processed? There is no evidence to suggest that the methods by which conventional pet foods are processed adversely affects their nutritional value. However, this is a concern often expressed by those who favour fresh or raw foods – for no valid reasons. So, I would agree that some may take exception to a claim that implies a lesser nutritional value of such foods.

We responded:

The definition of highly processed foods are manufactured products that are designed to have a long shelf-life through heat treatment or the addition of preservatives, colouring, additives and flavourings.

Extrusion is the process used by pet food manufacturers to turn ingredient mixes into kibble. The extrusion process involves extremely high temperatures. Research shows that drying pet food at 160 degrees C (320 degrees F) to 180 degrees C (356 degrees F) can significantly reduce its nutritional value. (1) In small-sized kibble (4 mm or about 0.16 inch), a drying temperature of 200 degrees C (392 degrees F) lowered concentrations of the amino acids proline, total lysine and reactive lysine.

Extrusion also markedly decreases concentrations of the linolenic (omega-3) and linoleic (omega-6) essential fatty acids and increases the concentration of oleic acid (omega-9 monounsaturated). The increase in oleic acid may point to lipid oxidation of the smaller kibbles during the drying process. Lipid oxidation can create off-flavours and aromas, as well as potentially toxic compounds.

According to a 2008 report by the Animal Nutrition Group at Wageningen University in the Netherlands, the extrusion process primarily destroys vitamin A, vitamin E and the B-group vitamins in dry food ingredient mixtures. (1)

Further studies show how the high temperatures used in the production of kibble (extrusion) lead to detrimental effects on nutrient quality and availability. There is a wealth of research regarding how processing methods subjecting food to high temperature and pressure have a detrimental effect, a widely accepted concept. Extrusion is specifically referenced throughout the scientific literature available to cause the physical removal of minerals during processing.

“Undesirable effects of extrusion include reduction of protein quality due to e.g. the Maillard reaction, decrease in palatability and loss of heat‐labile vitamins. Effects of extrusion processing on the nutritional values of feeds for livestock have been well documented.“ (2)

Applying heat, above 140 degrees centigrade, to carbs and proteins, always found in kibbles biscuits, will result in carcinogen production, heat-medicated toxins, through the Maillard Reaction. Starches (carbs) and protein (meats) fuse to form Advanced Glycation End products and Acrylamide: carcinogens. A 2013 paper intitled 'Should veterinarians consider Acrylamide that potentially occurs in starch-rich foodstuffs as a neurotoxin in dogs?' shows this (3). The Maillard Reaction does not happen with raw, dehydrated or fresh food because preparation temperatures are moderated.

1. Q. D. Tran, 2008, Extrusion processing: effects on dry canine diets, PhD Thesis, Wageningen University and Research Centre

2. Effects of extrusion processing on nutrients in dry pet food. Quang D Tran Wouter H Hendriks Antonius FB van der Poe. Science of food and agriculture, Volume 88, Issue 9

3. Should veterinarians consider acrylamide that potentially occurs in starch-rich foodstuffs as a neurotoxin in dogs? Le Roux-Pullen L1, Lessing D. J S Afr Vet Assoc. 2011 Jun;82(2):129-30.

Further references

- Nutritional Evaluation of Food Processing pp 319-354, Effects of Heat Processing on Nutrients, D Lund.

- International Journal of Food Science, Volume 2015, Article ID 526762, Food Processing and Maillard Reaction Products: Effect on Human Health and Nutrition. N Tamanna, N Mahmood.

- Impact of Processing on Food Safety pp 99-106. The Impact of Food Processing on the Nutritional Quality of Vitamins and Minerals, M Reddy, D Love.

- Nutritional Evaluation of Food Processing. E Karmas, R Harris.

And 6 weeks later our ad with these claims is approved and on TV!

For owners, it can be difficult to navigate the pet food field and we always recommend doing your own research, getting multiple opinions on an issue and taking a common-sense approach to the matter.