Animal feeds are formulated by means of least cost formulation. This requires the composition of the diet to be correct in terms of amino acids, minerals, energy and raw materials used. Up to date, it is not possible to adequately present a model which also takes into account specific properties of certain raw materials and which exert their effect on the physical quality of the manufactured feed. For example, one can think of hardness and durability of the feed, oil-binding properties, in case of fish-feed; water stability and (non-) buoyancy. This article will discuss the costs and benefits of using specific ingredients in relation with formulation and feed processing. Examples will be presented to show the various trade-offs that can be expected in terms of costs of raw materials, costs of manufacture and commercial benefits.