Low grade, controversial or vague ingredient we usually recommend avoiding
Derivatives of vegetable origin in dog food
Defined as "derivatives resulting from the treatment of vegetable products, in particular cereals, vegetables, legumes and oil seed", 'derivatives of vegetable origin' can refer to an extremely wide range of ingredients, from some of the best to some of the worst.
Although 'derivatives of vegetable origin' does not necessarily refer to a bad ingredient, it could and there's no way of knowing. It's vagueness also allows the manufacturer to change formula from one batch to another depending on what vegetable products are available at the time.
Because it is impossible to know what 'derivatives of vegetable origin' refers to, it is usually best to assume the worst and treat it with caution. This is particularly important if your dog is prone to dietary intolerance as identifying and eliminating problem ingredients is impossible unless you know exactly what you are feeding.