Pet food palatability is the result of what we at AFB International call “the triangle of palatability success”: ingredients, palatants and processing. Fats can provide important functions on all three sides of the triangle, something I see daily in my role as research and development director at AFB’s European headquarters in Oss, The Netherlands.
FATS IN INGREDIENTS
Fats may be naturally present in ingredients chosen for a pet food formulation. These fats can serve as a source of important Omega-6 and Omega-3 fatty acids, boosting nutritional value, as well as flavor for pets.
Pet foods that include Omega-6 and Omega-3 fatty acids in ratios between 10 to 1 and 5 to 1 have been shown to have health benefits, including reduced risk of heart disease, joint problems and other issues related to inflammation.
FATS AS PALATANTS
Fats can be applied topically or internally to pet food. The most common topically applied fats are animal fats. Chicken fat provides high palatability but also greasiness, while pork offers a less-greasy but less palatable alternative. Both chicken and pork fat have a low melting point, keeping them liquid at lower temperatures. Beef fat is used less often because of the need for a beef-free claim in many countries and because of its high melting point, causing it to become hard at temperatures from 20 to 25 degrees Celsius.
For total fat application, up to 8% may be used in a dry pet food formulation with a single-screw extruder. Fish and flaxseed oils are some examples of the most common fats used as internal palatants. Fats generally aren’t used internally at high application levels because of their negative effect on the expansion rate, which correlates to increased specific weight of the kibble.
FATS IN PROCESSING
Choosing a high-quality fat and processing it to maintain its quality is critical. Adding antioxidants immediately during the rendering process and maintaining a proper storage temperature before and after application are keys to success.
How fats are applied in pet food production is important, too. As noted, fat may be applied topically or internally, though topical application is used about 80% of the time. The most common processes for adding topical fats are drum coating, vacuum coating and spinning disk coating.
A fat often is combined with liquid or dry palatants—or both. When used in combination, the fat is applied first, then the liquid palatant, then the dry palatant. This order helps ensure the dry palatant will adhere better, as well as keeps the fat from masking the effect of the dry and liquid palatants.
For more detailed information on fats, including AFB results that show the difference between dogs and cats in fat level preference, see “Functions of Fat” in the Downloads area at afbinternational.com or email me at firstname.lastname@example.org.