Global consumption of seafood is predicted to increase to 182 million tonnes by 2030 (FAO 2022). Pressures to provide enough feed to supplement the growing aquaculture industry is detrimental to meet up with this production. Singapore relies heavily on imported fish feed for their aquaculture production, and feed cost attributes up to 40% of operation cost. Hence, finding alternative feed ingredients for fish feed is essential. In this study, discarded fish guts and fruit waste were utilized as alternative feed ingredients for a new formulated fish pellet.
Fish guts and fruit waste discarded by supermarkets and retailers were collected and powderised. Formulation of crude protein (cp) of the final pellets from these two feed ingredients were set at 30% cp levels, along with different proportions of wheat starch as binder for the two main ingredients. Formulated pellets were subjected to pellet solubility tests and nutrient analyses of fatty acid, protein, and amino acid profiles, against a commonly used commercial tilapia feed from Uni-president® as a controlled comparison.
Preliminary results show significant increases in the levels of fatty acids, including omega 3, 6, and 9 fatty acids, along with similar levels of crude protein were found in our formulated feed in comparison to the commercial fish feed, with all essential amino acid requirements met. Solubility tests revealed the treatment with 15% wheat starch had the least variance in terms of weight loss of a pellet before and after soaking for 120 minutes.
These results infer that our feed formulated with recycled fish guts and fruit waste could produce a sustainable substitute fish feed that provides the necessary nutrition for food fish.