A dramatic gain in efficiency is an absolute necessity if we are to overcome the agricultural challenges of the third millennium. One of the ways that could lead to such a gain in efficiency is a renewed and augmented use of by-products.
In an agricultural context the food industry is a major source of potentially valuable by-products. For other Western European countries VALORBIN (2003a) mentions 5 million tons in Denmark, 11 million in The Netherlands, and 14 million tons in Germany. 70 to 80 % of food industry by-products are reused in feed manufacturing.
In all applications, two important ethical aspects seem to overarch all others, being (the care for) public health, and the need for recycling. Both aspects will be important with all by-products and all applications, but their relative importance will differ. This does not mean that zero-risk or maximum recycling need to be the goal. In both aspects environmental considerations are included. It is important to keep an eye out for direct and indirect impacts on other products.
A hierarchy seems to exists, in which reuse as food has priority over use as feed or biomass (energy or green chemistry), and with a sustained faith as waste as the least preferable option.
The by-products that one wants to use in feed production, will have to be selected based on type (e.g. category 3 animal by-products should be safe), traceability (single sourced products are preferred) and goal (e.g. is the target animal omnivorous).
What Are Nutrient-Dense Fish Feeds and Their Importance in Aquaculture?
