Formulation and Ripening Duration of Italian-Style Ostrich Salami: Impact on Physicochemical Quality and Sensory Traits

The present research investigated the effects of two pork back-fat concentrations (30% fat, FAT30, and 40% fat, FAT40), two sodium chloride levels (2.4% and 2.6%), and two starter culture combinations (Lactobacillus curvatus/Staphylococcus xylosus; LAB6, and Lactobacillus sakei/Staphylococcus xylosus; LAB8) on ripened ostrich salami. Salami samples were formulated without nitrite and nitrate, which aligns with consumer demands for healthier, cleaner-label meat products. It is specified that the present experiment is structured with a single-batch-per-treatment combination: this was due to structural processing limitations in the production facility, which was an artisanal laboratory and not an industry plant. After 10 weeks of ripening, FAT30 salami showed higher values of pH, salt content, water-phase salt (WPS), α-tocopherol, free fatty acids (FFA), and secondary lipid oxidation products (TBARS) compared with FAT40 salami. Conversely, FAT40 salami exhibited higher water activity (aw), moisture-to-protein ratio (M:P), conjugated dienes (CD; primary lipid oxidation products), and non-protein nitrogen (NPN) than FAT30 salami. Both NaCl concentration and starter culture type influenced several of the measured variables. Specifically, salami containing 2.4% salt exhibited higher FFA and CD values than the formulation containing 2.6% salt. Likewise, the LAB8 starter culture resulted in higher CD and NPN levels compared with LAB6. Fat inclusion level significantly affected sensory characteristics. FAT40 salami exhibited greater intensities of gamy, metallic, fatty, and moldy flavors, as well as higher overall off-flavor intensity, tenderness, and juiciness. In contrast, FAT30 salami was characterized by greater cohesiveness and a more pronounced ripening flavor. The 2.6% sodium chloride treatment resulted in greater color homogeneity, higher odor intensity, and stronger rancid notes, while reducing the perception of metallic, fatty, and moldy flavors compared with the 2.4% treatment. Salami inoculated with LAB6 exhibited a higher intensity of off-flavors than the formulation produced with LAB8. Moreover, several significant interactions among the three experimental factors were observed. After 20 weeks of ripening, the effects observed after 10 weeks for most physicochemical parameters were largely maintained. However, FFA and CD concentrations (both below the limit of quantification) no longer differed between the two fat inclusion levels. Sensory evaluation revealed that the differences between FAT30 and FAT40 in undesirable flavor attributes disappeared over time, whereas the perception of ripening and maturity became even more pronounced in FAT30 salami. Regarding FA composition, FAT30 salami contained higher proportionsof saturated FA and polyunsaturated FA, whereas FAT40 salami was characterized by a higher monounsaturated FA content and more favorable lipid quality indices.