Biotechnological approaches to obtain cricket powder hydrolysates for the formulation of innovative bakery products.

Edible insects are over 2000 species and are traditionally consumed in different parts of the world (Africa, Asia, Central and South America). They constitute a valid food resource since they are characterized by high nutritional values in terms of proteins, fats, vitamins and minerals. However, their use is still limited since they are not well perceived, and they are characterized by high chitin contents which limit their technological functions. In this perspective, principal aim of this research was to use Debaryomyces hansenii and Yarrowia lipolytica strains, previously characterized and selected, to obtain a cricket powder based hydrolyzed to be use as ingredient for innovative bread production. The cricket powder hydrolyzed was obtained according to the method of Patrignani et al [1]. Specifically, the hydrolysed obtained from Y. lipolytica PO11, RO25 and D. hansenii SP6L12 were added to the dough at the concentration of 15 and 25%. The hydrolysate-based doughs and baked products obtained were compared with controls containing the cricket powder obtained in the same way of the hydrolyzed but without the use of selected yeast. The chitin content was evaluated on the three types of hydrolysate and on the control. The microbiological composition, the protein profile and the volatile molecules content were evaluated on the doughs before and after rising with Saccharomyces cerevisiae LBS, according to. The texture and sensorial profiles were also evaluated on the products obtained after cooking.The obtained data showed the capacity of the Y. lipolytica and D. hansenii strains to differently characterize cricket powder hydrolysates due to the different growth potential, specific proteolytic activities and different production of volatile molecules. Microbiological analyses evidenced a higher growth potential of Y. lipolytica in cricket powder and water than D. hansenii strain. Y. lipolytica RO25 showed a higher reduction in chitin content and pH. Furthermore, the results highlighted the significant proteolytic properties of the tested strains. Hydrolysates were characterized by higher protein degradation and richer protein hydrolysis profiles. The obtained doughs were also qualitatively different and characterized by specific fingerprinting. Specifically, all the percentage of Y. lipolytica PO11 hydrolysate-based doughs, were characterized by peculiar aromatic compounds, including furanones. In addition, sensory analysis and texture analysis data highlighted the good application opportunities of cricket powder based hydrolysates as ingredients for bread making. The choice of a specific strain in food sector will be linked to the sensory, qualitative and nutritional characteristics which have to be imparted to the final product, also considering the production process adopted.