Enhancing Functional and Nutritional Properties of Cricket Powder Through Solid-State Fermentation: Sustainable Protein Applications and Industrial Potential

Crickets (Acheta domesticus) have recently attracted significant attention worldwide as a sustainable source of protein in both the food and feed sectors. Compared with traditional animal protein sources, cricket farming requires considerably less water and land, while producing far lower greenhouse gas emissions than cattle, sheep, and other livestock. From an environmental perspective, crickets offer a compelling advantage as an alternative protein source. Cricket powder, derived from whole crickets, is rich in protein, containing 57% to 70% of dry matter, and provides a complete profile of essential amino acids, particularly high in leucine and valine, although tryptophan is relatively limited. In addition to proteins, cricket powder contains a variety of fatty acids, including omega-6 polyunsaturated fatty acids and a significant proportion of saturated fatty acids such as stearic acid and palmitic acid. It is also a source of dietary fiber, essential minerals, and B vitamins. Once processed into powder, cricket protein can be incorporated into a wide range of foods such as pasta, bread, and snacks, providing an opportunity to enhance the nutritional profile of conventional products.

Despite its high nutritional value, cricket powder has certain limitations in its functional properties, including relatively low foaming capacity, emulsifying ability, gel formation, and water retention. These limitations pose challenges for food processing and the quality of final products, making the improvement of cricket powder's functional properties a key focus of food science research. One promising approach is solid-state fermentation (SSF), in which microorganisms are cultured on solid substrates with low moisture content, unlike conventional submerged fermentation. Filamentous fungi are particularly suitable for SSF, as they can effectively transform the substrate, modify protein structures, and enhance functional properties while increasing flavor and nutritional value. In this study, two edible fungi, Pleurotus ostreatus (oyster mushroom) and Rhizopus oligosporus, were selected to investigate the effects of SSF on the nutritional composition and functional characteristics of cricket powder. These fungi were chosen not only for their food safety but also for their high consumer acceptance; for instance, R. oligosporus has a long history of use in traditional Southeast Asian fermented foods like tempeh, while P. ostreatus is among the most widely consumed edible mushrooms globally. The use of well-known edible fungi helps ensure regulatory approval and facilitates market acceptance.

Commercial cricket powder was first subjected to heat treatment at 121°C for 15 minutes to ensure microbiological safety and create favorable conditions for subsequent fermentation. Although heat treatment can cause irreversible protein modifications, it was found in this study to significantly enhance the foaming properties of the powder, increasing foaming capacity by more than sixfold. The heat-treated powder was then inoculated with either P. ostreatus or R. oligosporus for solid-state fermentation. Fermentation significantly altered both the nutritional composition and functional properties of the cricket powder. Total protein content decreased by 5% to 11% due to partial hydrolysis into smaller peptides and free amino acids; however, the overall essential amino acid profile remained largely intact. The analysis revealed that sulfur-containing amino acids became the limiting amino acids in the fermented powder. Notably, R. oligosporus fermentation was particularly effective in reducing fat content by approximately 35% and improving protein solubility and emulsion stability. Meanwhile, P. ostreatus fermentation enhanced foaming capacity and water absorption. These findings indicate that appropriate microbial fermentation can substantially improve the functional properties of cricket powder, making it more suitable for a wider range of food applications.

Fatty acid composition also changed during fermentation. While total fat content decreased, both fungi slightly increased the proportion of saturated fatty acids, likely due to microbial lipid metabolism. These changes are important for regulating flavor and texture, as fatty acid composition directly influences the sensory quality and stability of food products. Moreover, fermentation can produce flavor-active compounds such as short-chain organic acids and bioactive peptides, which may enhance the palatability of cricket powder and improve consumer acceptance. Given that insect-based proteins face cultural and psychological barriers in Western markets, functional modification via fermentation not only enhances technological properties but also supports broader market adoption.

From an industrial perspective, cricket powder holds significant promise. Its high protein content and complete amino acid profile make it suitable for incorporation into functional foods, protein supplements, and sports nutrition products. With solid-state fermentation improving its functional characteristics, cricket powder can be applied in high-protein breads, cookies, protein beverages, meat analogues, and even dairy alternatives. Enhanced foaming and emulsifying capacities allow it to partially replace egg white or dairy proteins in formulations, providing diverse options for vegetarian, vegan, and environmentally conscious consumers. Furthermore, fermentation may improve the bioavailability of minerals and break down indigestible components such as chitin, increasing overall nutritional value.

Future research could explore the optimization of functional properties through multi-strain or sequential fermentation strategies, evaluating parameters such as temperature, moisture content, and fermentation duration. Sensory evaluation and consumer acceptance studies will also be crucial for commercial adoption. Additionally, combining solid-state fermentation with other processing techniques, such as enzymatic hydrolysis or high-pressure treatment, could further enhance the applicability and nutritional profile of cricket powder. As global demand for sustainable protein rises, functionalized insect proteins may play an increasingly important role in diversified and environmentally friendly food systems, addressing both population growth and ecological pressures.

In conclusion, cricket powder is a highly nutritious and sustainable protein source, rich in essential amino acids and bioactive compounds. While its intrinsic functional properties are limited, heat pre-treatment and solid-state fermentation significantly enhance foaming, emulsifying, protein solubility, and water absorption capacities. P. ostreatus and R. oligosporus provide complementary benefits, maintaining nutritional integrity while improving processing performance. These findings not only offer scientific guidance for industrial applications of insect protein but also provide a roadmap for innovation in sustainable and functional protein development. By integrating edible insect proteins with microbial fermentation, the food industry can expand its toolkit for sustainable nutrition, functional food design, and environmentally responsible protein alternatives. This approach demonstrates the potential of insect-based ingredients to contribute to the future of global food security, offering both technological versatility and ecological benefits.