Optimization of rearing conditions for house cricket (Acheta domesticus) to produce nutrient-rich flour as a novel food and feed ingredient

Abstract In recent years, the demand for alternative protein sources has been increasing due to global population growth and the unsustainable production of conventional proteins. Edible insects are gaining attention in both the food and animal feed industries. This trend is supported by the European Union’s regulatory framework, which facilitates and promotes insect farming for human and animal consumption. Acheta domesticus is an insect approved for use in both human and animal nutrition. This study aimed to optimize its rearing conditions to produce nutritionally valuable flour for food and feed applications. Agricultural by-products, such as carrots and cabbage, along with food industry residues like flaxseed oil cake and wheat bran, were used as rearing substrates. The obtained results indicate that cricket flour is a high-protein ingredient, containing 64-73% protein and 17-24% fat. It has a well-balanced amino acid profile, with methionine as the limiting amino acid. The mineral composition is suitable for both human and animal consumption, with sodium (Na), potassium (K), and phosphorus (P) being the most abundant. The flour is rich in polyunsaturated fatty acids (PUFA), and the addition of flaxseed oil cake increased the omega-3 fatty acid content by 30-fold. Rearing parameters, such as duration and substrate composition, significantly influenced the nutritional profile of the flour. Multi-objective optimization revealed that the most nutritionally balanced flour is obtained when Acheta domesticus is reared on a mixture of cabbage, carrots, wheat bran, and flaxseed oil cake for 60 days. Optimizing rearing conditions, including substrate composition and duration, is crucial for obtaining the highest nutritional value. This study confirms that cricket flour can be tailored for specific dietary needs, reinforcing its role as a viable and sustainable ingredient in modern food and feed production.