Combined effects of starter cultures and formulation variables on physicochemical and oxidative stability of smoked bacon during storage at 22 °C

Abstract Smoked bacon is a meat product susceptible to physicochemical and microbiological changes during storage, which may compromise its quality and safety. This study evaluated the effects of different formulations combining starter cultures—SafePro B-LC-78 ( Pediococcus acidilactici and Staphylococcus carnosus , TA) and a combination of two commercial starter culture systems (SafePro B-2 and BactoFlavor ® Rosa, containing Latilactobacillus sakei , Staphylococcus vitulinus , and Staphylococcus xylosus , TB), applied according to manufacturer recommendations, along with different sugar types and concentrations, compared with a non-inoculated control (TC), on the technological, microbiological, color, and oxidative stability of smoked bacon stored for 120 days at 22 °C. The smoking process ensured an internal temperature ≥ 52 °C and weight losses ranging from 19.6 to 19.9% for all treatments ( p > 0.05). Throughout storage, TA and TB showed a more pronounced pH reduction and lower water activity and syneresis values compared with the control, suggesting improved physicochemical stability under the tested conditions ( p < 0.05). Lactic acid bacteria counts were influenced by both native microbiota and starter cultures, likely reflecting differences in substrate availability associated with formulation composition, with no consistent significant differences among treatments over time. Colorimetric analyses revealed greater color stability in TA and TB, with lower total color difference (Δ E ) and chroma C * values than those observed in TC ( p < 0.05). Peroxide values were lower in TA (1.05 mEq O 2 /kg) and TB (1.35 mEq O 2 /kg) compared with the control (2.12 mEq O 2 /kg), indicating reduced lipid oxidation. Treatment TB was associated with improved color stability, while TA showed greater oxidative stability during storage. Overall, the results indicate that the observed effects are related to the combined influence of starter cultures and formulation variables (including sugar type and concentration). TB exhibited a distinct combination of stability-related attributes; however, this behavior should be interpreted in the context of the interaction between microbial composition and formulation factors.