# Effect of Fermentation Technology and Storage Time on the Quality of Salami-Type Sausages
## 3 Results and Discussion
### Influence of Fermentation Technology on the Microbiological Characteristics of Salami-Type Sausages
Obtaining low water activity is an essential indicator of the safety of fermented meat products. To prevent the growth of undesirable microorganisms, i.e., _Clostridium botulinum_ and _Salmonella_, it is necessary to quickly reduce the a\({}_{\text{w}}\) value to the desired level (<0.96 and <0.94, respectively). According to the United States Department of Agriculture (USDA), no formal definition of \"dry\" and \"semidry\" sausages exists. Dry sausages are characterized by a final water activity of 0.85-0.91, and semidry sausages are in the range of 0.90-0.94. It is also assumed that raw dried sausage can be stored at room temperature if its water activity is lower than 0.91 [46,52]. In the present study, the pH of the sausages produced using \"warm\" technology immediately after ripening was 5.07 (Table 4). The obtained results are consistent with the study by [PERSON] [53]. Lactic acid production (by LAB during fermentation) reduces the pH value of the sausage, inhibits the growth of spoilage organisms, and promotes the formation of the flavor and color of the sausage. During storage, the value of this parameter decreased to 4.92 (Table 3). In the case of salami-type sausages produced by \"cold\" fermentation, a significantly lower pH value (4.87) was determined than for \"warm\"-fermented sausages. In addition, after 63 days of storage, a further decrease in pH to 4.81 was noted (Table 4). \begin{table}
\begin{tabular}{c c c c c} \hline \multirow{2}{*}{**Fermentation Technology**} & \multicolumn{4}{c}{**Storage Time [Days]**} \\ \cline{2-5}  & **0** & **21** & **42** & **63** \\ \hline \multicolumn{5}{c}{Water Activity [-]} \\ \hline Warm & 0.855 \(\pm\) 0.003 bA & 0.857 \(\pm\) 0.006 bA & 0.854 \(\pm\) 0.010 bA & 0.834 \(\pm\) 0.006 aA \\ Cold & 0.858 \(\pm\) 0.006 aA & 0.858 \(\pm\) 0.007 aA & 0.865 \(\pm\) 0.006 aA & 0.868 \(\pm\) 0.008 aB \\ \hline \multicolumn{5}{c}{pH Level [-]} \\ \hline Warm & 5.07 \(\pm\) 0.06 aB & 4.97 \(\pm\) 0.03 aA & 5.03 \(\pm\) 0.04 bB & 4.92 \(\pm\) 0.03 aB \\ Cold & 4.87 \(\pm\) 0.01 aB & 4.95 \(\pm\) 0.09 bA & 4.81 \(\pm\) 0.02 aA & 4.81 \(\pm\) 0.04 aA \\ \hline \multicolumn{5}{c}{Acid Value [mg KOH/g of fat]} \\ \hline Warm & 7.03 \(\pm\) 0.53 aB & 11.05 \(\pm\) 0.15 bB & 11.25 \(\pm\) 0.76 bB & 11.08 \(\pm\) 0.05 bB \\ Cold & 4.45 \(\pm\) 0.27 aA & 4.87 \(\pm\) 0.20 aA & 7.39 \(\pm\) 0.15 bA & 7.28 \(\pm\) 0.15 bA \\ \hline \multicolumn{5}{c}{_TBARS_ [mg MDA/kg of product]} \\ \hline Warm & 0.88 \(\pm\) 0.05 bB & 1.06 \(\pm\) 0.01 cB & 0.76 \(\pm\) 0.01 aB & 0.87 \(\pm\) 0.02 bB \\ Cold & 0.62 \(\pm\) 0.10 bA & 0.64 \(\pm\) 0.03 bA & 0.38 \(\pm\) 0.01 aA & 0.47 \(\pm\) 0.01 abA \\ \hline \end{tabular} Different lowercase letters between mean values \(\pm\) standard deviations in the row indicate significant differences (grouping variable: storage time), \(p\leq\) 0.05. Different uppercase letters between mean values \(\pm\) standard deviations in the column for a given parameter indicate significant differences (grouping variable: fermentation technology), \(p\leq\) 0.05.  
\end{table} 
Table 4: Changes in the physicochemical and chemical properties of salami-type sausages fermented with “warm” and “cold” technology, stored for 63 days. The examined salami-type sausages meet the criteria for durable dry sausages in terms of water activity (\(\leq\)0.90) and pH (\(\leq\)5.3) [54]. These products can be considered safe and stored at room temperature. This is also consistent with the manufacturer's declaration on the label of the sausages fermented using the \"warm\" method. Due to the high content of fat in the produced salami-type sausages (see Table 3) and the significant influence of fat and its derivatives on the sensory properties of the final products, the degree of hydrolysis (acid value--AV) and the secondary degree of oxidation (TBARS index) of this component were determined.