The contribution of sturgeon species and processing conditions on caviar texture, metabolomic profile and sensory traits

A comprehensive evaluation of the attributes that determine caviar quality, including sturgeon species and processing methods, is still lacking in the scientific literature. In this study, eight types of caviar, obtained from six different sturgeon species and produced using either salt or a combination of salt and sodium tetraborate (E285) with pasteurization, were characterized through untargeted metabolomics, sensory analysis, and texture evaluation. The results showed that Huso huso caviar was rich in gamma-glutamyl peptides (contributing to a kokumi taste), while the other sturgeon species were primarily distinguished by lipids (mainly glycerophospholipids) and nucleotides (such as AMP, inosinic acid, and other metabolites driving umami taste). Moreover, untargeted metabolomics revealed the technological effects of salting and pasteurization. Sensory analysis identified crunchiness, color homogeneity, and darkness as the main traits differentiating the products. Butter, hazelnut, and briny flavours were also key characteristics of the caviar.