Characterisation and valorisation of solid food waste into quality, safe, palatable and digestible feed for sustainable edible insect (House Cricket) protein production

Abstract

Globally, commercial feed production relies on conventional food resources. By 2050, nearly half of the world's grain production will be allocated to feed. This unsustainable trend poses significant risks to food security in developing countries, such as Uganda. To mitigate this conflict, second-generation biomass, such as food waste can be a viable alternative. With Uganda generating and discarding approximately 300,000 tonnes of food waste annually, the aim of this study was fivefold, i.e., (1) characterise the nutritional and microbial composition of solid food waste materials; (2) develop a process to valorise food waste into a cricket feed; (3) ascertain the nutritional quality of the developed feed; (4) establish the microbial load of the feed; and, (5) test the palatability and digestibility of the formulated feed. Four feed formulations were developed, with proximate analysis indicating 17.79–28.00% protein; 6.19–13.53% fat; 3.00–6.16% fibre; 5.41–14.21% ash; and 48.72–62. 38% carbohydrates, comparable to amounts in the control feed. After heat treatment, the counts (log cfu/g) for total plate (6.4–6.8), yeast and mould (3.4–4.1), Enterococcus (4.4–6.9), and Staphylococcus aureus (4.5–4.8) were similar to those observed in the literature, while no Salmonella typhi was detected. The experimental feeds demonstrated higher palatability (18 g/d) and significantly higher digestibility (86–87%) compared to the control. The conversion of food waste into feed for crickets, an alternative protein, potentially contributes to resolving food-feed conflicts while promoting planetary resource use efficiency in the long run.