Quality characteristics of nitrite-free emulsified pork sausages with gardenia red-based additive combinations

This study evaluated the effects of gardenia red (GR), vitamin C, and sodium caseinate, applied alone or in combination, on the quality characteristics of nitrite-free emulsified pork sausages. Four treatment groups were prepared: CON (0.01% sodium nitrite), T1 (0.04% GR), T2 (0.04% GR with 0.05% vitamin C), and T3 (0.04% GR with 0.05% vitamin C and 0.4% sodium caseinate). GR-containing treatments significantly increased redness (a*) and decreased lightness (L*) compared with CON, and T2 showed the most intense redness. T3 exhibited the greatest improvements in emulsion stability, water and fat retention, and initial texture. Oxidative stability was enhanced in both T2 and T3, which showed significantly lower TBARS values than T1. In contrast, microbial counts and VBN values were higher in the GR-treated groups, especially in T3, indicating that these combinations did not provide microbial control comparable to sodium nitrite. Residual nitrite was detected only in CON, confirming complete nitrite removal in all GR formulations. Overall, GR-based additive combinations improved redness, oxidative stability, and initial texture properties in nitrite-free sausages. However, because they lacked microbial inhibitory activity, these additives should be regarded as quality-enhancing components rather than complete nitrite substitutes. Additional preservation strategies are required to ensure microbial safety in nitrite-free sausage production.