Ideally superior commercial foods should have none of the following:
Grains of any kind, not even rice. Yes, rice is a grain. And no brown rice isn't any better than white when it comes to cats. It's all unnecessary and in many cases, harmful. We've had cats on the list with projectile vomiting and other types of abdominal distress from brown rice and other grains.
Fruits - cats have not evolved eating fruits yet some brands include apples, persimmons and other fruits. A few even contain tomatoes, which unless very ripe can be downright harmful to cats. Certain medicinal herbs are also often added by manufacturers to purportedly confer health benefits e.g. cranberries and blueberries for bladder health. There is no evidence that cats derive any such benefit from various additions. They're at best unnecessary.
Whether inclusion of fruits and herbs e.g. garlic, alfalfa, cranberries, take a brand out of the running is a judgment call. If the amount is very small, and the rest of the ingredients are good, write to the manufacturer asking for it to be removed, and/or feed it in rotation.
Fillers such as powdered cellulose, peanut hulls, and grain sorghum which have no nutritional value.
Non-meat proteins such as potato protein, soy protein isolate, corn gluten, or the infamous rice gluten and wheat gluten part of the recent pet food recall. These all artificially boost protein levels on paper but lack the amino acid profile of meat, and thus are useless, not to mention detrimental to cats' health. For example, soy protein has been implicated in hyperthyroidism, and also shown to increase the excretion of taurine by cats' bodies.
Dyes/colorings e.g. Caramel color, titanium dioxide, and red dyes #2 and 40, flavoring, or synthetic preservatives such as BHA, BHT, and ethoxyquin.
Vegetables only if less than 10% of the formula, and if cat isn't allergic
Fish, but only if the manufacturer specifies it is "human-grade". Also look for fish lower on the food chain e.g. sardines, as opposed to tuna. Reports such as this one from the FDA can be used as a guide: professional resume writing vancouver
What superior cat food should contain:
Meat (preferably human-grade, even better if it is organic) as the first ingredient, not "byproducts" which can mean just about anything other than muscle meat. Sometimes this means offal and other times who knows:<
A specific meat source preferably not just for muscle meat but also for organs e.g. stating they are from animal x or y, not "poultry" which could refer to a number of different meats.
Small amount of organ meat such as kidneys or liver, since they have a different nutrient profile than muscle meat