Food loss and food waste recovery as animal feed: a systematic review

While society struggles to meet increasing food demand and mitigate food security challenges, approximately one-third of the food produced globally is lost or wasted every year. Using food wastes as animal feed offers a solution that simultaneously addresses waste management and food security challenges while reducing the pressure to grow conventional feed, both a resource and environmental burden. The present systematic review examines the available literature discussing the feasibility of incorporating food waste in feeds for fish, swine, poultry, rabbits, and ruminants while also assessing related safety and logistical concerns. Results suggest that various types of food losses and wastes are generally nutritious and can be converted into safe feeds by modern technologies and can be incorporated into animal diets. Animal growth performance in response to various food loss and/or waste substitution rates depends on tested feed sources, animal species, age, and length of the feeding trials. Overall, animals fed with waste-based feeds had comparable feed conversion ratios to those grown using conventional feeds. However, research should focus more on characterizing nutrient variability of food losses and wastes and developing efficient and timely waste collection and transport procedures. The present review concludes that partial incorporation of food waste into animal feed is a viable solution to mitigate food wastage without compromising animal growth or health.