Optimizing <i>Enchytraeus albidus</i> Production With Agri‐Food Waste: A Nutritional Landscape Approach

With aquaculture playing an increasingly important role in global food systems, there is a pressing need for feed innovations that can support industry growth without exacerbating overfishing or environmental degradation. The white worm, Enchytraeus albidus , is a promising substitute live feed candidate capable of growing on a variety of organic waste materials. This study explores the effects of agri‐food waste products on the biomass yield, juvenile production, and nutritional composition of E. albidus . Using a nutritional landscape approach, we found that white worm cultures fed baking yeast and oatmeal yielded the highest biomass, while cultures fed fat‐reduced oatmeal, spent brewer’s grain, and oatmeal produced the most juveniles. This approach proved valuable for identifying optimal nutrient combinations and visualizing how dietary trade‐offs shape growth and reproduction across diverse feed inputs. Diets containing 10%–75% protein, 30%–85% carbohydrate, and 0%–40% lipid, respectively, optimized biomass production, with protein and carbohydrate content serving as critical limiting factors. Juvenile production was primarily influenced by carbohydrate content, with at least 50% carbohydrate needed to achieve more than 85% of the reproduction observed in the control. Feed treatments significantly affected the macronutrient composition of the worms, with high‐lipid diets, such as coffee grind and rape seed oil, increasing total fatty acid content. These findings demonstrate the potential of utilizing no‐ or low‐cost feedstock to optimize E. albidus cultivation, providing a cost‐effective and sustainable fish feed alternative that could help reduce reliance on marine‐derived resources in aquaculture.