Corn is a High-Quality, Nutritious
Pet Food Ingredient

One myth surrounding commercial pet foods concerns the digestibility and nutritional value of corn. A common misconception regarding corn is that it is a low-quality food ingredient, or filler, which contains minimal nutritional value. This Nutrition Brief will address the topic of corn as a valuable ingredient of pet food and show why this diverse grain is an excellent source of protein, carbohydrates, and essential fatty acids.

High-Quality Protein Source

Cells of the body utilize amino acids from multiple sources:

  • Food proteins
  • Single amino acids added to food
  • Amino acids synthesized in the body

Salmonella Contamination

Cells cannot distinguish whether amino acids from food proteins are provided by plants or animals. At Purina we complement highly digestible animal protein with a natural plant protein source like corn, to deliver all of the essential amino acids that pets need. Plant protein sources can provide highly digestible, high quality dietary protein for dogs and cats if they are properly processed. Corn is a good example. Utilizing a wet milling process, the corn kernel is separated into starch, fiber and protein components. The protein component becomes corn gluten meal, a source of highly digestible protein for dogs and cats.

Also a High-Quality Carbohydrate Source

Dietary carbohydrates play an important role in pet foods because they provide an energy source for the animal, thus allowing the proteins in the diet to be used to meet the animal’s amino acid requirements rather than its energy needs. Corn is a very useful ingredient in pet food because it is a high-quality source of carbohydrates as well as protein. Corn meal, a major source of carbohydrate in pet food, contains approximately 75% carbohydrates.

Carbohygrate Conentration in Corn Meal VS. Corn Gluten Meal

Highly Digestible

Appropriate nutrient levels are very important in a balanced diet. Of equal importance is the digestibility of the nutrients, as this important first step can be the rate-limiting factor in the total bioavailability of the food. 3, 4

Digestibility of Key Ingredients

Antigenicity of Corn

Another common misconception regarding the use of corn in pet food is that corn is highly antigenic and will cause food allergies. In fact, a study in Veterinary Dermatology looked at the frequency with which specific food ingredients caused a reappearance of pruritis during a food elimination trial, and corn had the lowest percentage of frequency cited. 5 (Some dogs reacted to more than one ingredient.)

Frequency of Specific Food Ingredients

Essential Fatty Acids

Corn is the only grain commonly used in pet food that contains linoleic acid, an essential fatty acid required by both dogs and cats for healthy skin and hair.

Antioxidant Activity

Antioxidants in the diet help to reduce cell damage in animals and people. Vitamin E is a major fat-soluble antioxidant, and corn oil is a major source of vitamin E. In a human study conducted by the Institute of Nutritional Science, University of Vienna, Austria, a diet containing corn oil was found to reduce DNA damage more effectively than a diet containing an olive/sunflower oil combination. 6

It is commonly thought that processed ingredients have a lower nutritional value than fresh ingredients. However, a study conducted by Cornell University found that cooking corn at 150 degrees Celsius for 50 minutes actually increased its antioxidant levels by as much as 53%. 7

High-Quality Corn

The quality of corn in pet foods can vary greatly. There are five grades of corn quality according to the USDA; grades 1 and 2 are traditionally utilized for human food products. 8 Nestlé Purina only selects grades 1 or 2 corn for all of its pet foods.

1. Small Animal Clinical Nutrition, 4th ed., p. 141.
2. Feed Commodity Bulletin. Oklahoma State University, Stillwater
3. Murray, et al. “Raw and Rendered Animal By-Products as Ingredients in Dog Diets”. Journal of Nutrition, Vol 128, No. 12, Dec. 1998: pp. 2812S-2815S.
4. Department of Agricultural Food and Nutritional Science. University of Alberta, Edmonton.
5. Jeffers, J.G. “Results of Dietary Provocation in Dogs with Food Hypersensitivity”. Veterinary Dermatology, Vol. 5, No. 3, 1994.
6. Elmadfa, I.; Park, E. “Impact of Diets with Corn Oil or Olive/Sunflower Oils on DNA Damage in Healthy Young Men”. European Journal of Nutrition, Vol 38 No 3, Dec. 1999: pp. 286-92.
7. Dewanto, V.; Wu, X.; Liu, R. H. “Processed Sweet Corn Has Higher Antioxidant Activity”. Journal of Agriculture and Food Chemistry, Vol 50 No 17, 2002, pp. 4959-4964.
8. USDA Nutrient Webpage: http://www.rahul.net/cgi-bin/fatfree/usda/usda.cgi

1234567891011