Commercial pet food is a massive industry, and for many pets it may be the only food they ever eat. It's often recommended by vets as a suitable food source, and given the large number of flavors and dietary options, there are varieties for every type of pet owner, discerning or conservative. Its manufacture, however, is often held up for scrutiny; while many manufacturers follow strict quality guidelines, and there are regulations in place to protect pets and owners alike, some corporations will always cut corners to maximize output and minimize costs.
Meat is used in nearly all commercial pet food, but it's rendered to remove the moisture and fat. The rendered meat may have additional components added to turn it into meat meal. Vitamins and minerals are also added to the mix, as well as, in some cases, artificial flavors, stabilizers and preservatives. All of the ingredients and additives are required by the FDA to be "Generally Recognized As Safe" or otherwise approved as food additives. Care must be taken if the ingredients include items such as grains and other fillers, as each pet's dietary needs should be considered uniquely.
The ingredients are ground and mixed, then put through a process known as high-heat extrusion. First, they are pre-conditioned with liquid fat, then put in a pressurized steam-filled drum. The mixture is cooked and passed through a form, cut to size, then cooled. The final product may then be sprayed with fat or flavor to make it more appealing. At this point, extra vitamins and minerals may be sprayed on the food as well, to compensate for the destruction of these compounds during high-heat cooking.
Commercial pet food labels are strictly regulated by the FDA and must indicate several qualities about the food itself. The name of the product itself must follow a specific format based on the quantities of specific ingredients. If a commercial pet food product contains 95 percent of a specific ingredient, it can be named using just that ingredient, such as "Chicken for Cats." If the ingredient makes up between 25 and 95 percent of the product, a descriptive word in the name is required; "Chicken Dinner for Cats," therefore, has less chicken in it than "Chicken for Cats." An item present in 3 to 25 percent concentrations is listed as being "with" the main ingredients -- "Chicken Dinner with Seafood" -- and an item that is present in smaller amounts but is detectable is defined as a flavor, such as in "Chicken Dinner with Seafood Flavor."
Byproducts and Unusual Ingredients
Commercial pet food often includes meal ingredients, and these are a source of great controversy. Meal is primarily ground meat or grains, but with added components that may include bone, organs and other products not generally consumed by humans. House pets, like their wild counterparts, generally have no qualms about eating these less savory ingredients, but many consumers feel upset when they learn of their presence and would prefer their pet only eat quality meat. In this situation, some consumers choose to make their own pet food.