## 4 Discussion  
In the course of the measurements, an initial series of experiments was conducted to examine the dominant and spoilage-causing microbes of the two tested sweet potato varieties. Subsequently, an investigation was conducted to ascertain the growth and survival of these microbes during storage and as a consequence of the various treatments with the extracts. As demonstrated in the scientific literature, the initial microbiota of fresh vegetables consists of _Aeromonas, Bacillus, Clostridium_, coryneforms, _Enterobacter_, _Erwinia_, _Flavorbacterium_, _Pantoa_, _Pseudomonas_, lactic acid bacteria, and _Xanthomonas_. Studies have observed that predominant spoilage microorganisms of refrigerated minimally processed vegetables stored under VP and modified atmosphere packaging (MAP) conditions are lactic acid bacteria, with _Leuconstoc mesenteroides_ being a notable representative [48]. \begin{table}
\begin{tabular}{c c c c c c c} \hline  & **Control** & **AP** & **CP** & **AA** & **CA** \\ \hline \multicolumn{6}{c}{\(\Delta\)E*} \\ \hline Bonita & on day 7 compared to day 0 & 5.54 & 9.44 & 3.72 & 17.26 & 10.17 \\  & on day 7 compared to the untreated sample & & 5.44 & 6.16 & 5.91 & 6.03 \\ \hline Covington & on day 5 compared to day 0 & 6.37 & 9.08 & 11.33 & 12.55 & 13.66 \\  & on day 5 compared to the untreated sample & & 6.12 & 2.89 & 1.82 & 1.94 \\ \hline \multicolumn{6}{c}{Browning index (BI)} \\ \hline Bonita & on day 7 compared to day 0 & 3.31 & 2.31 & \(-\)0.15 & 2.76 & \(-\)2.61 \\  & on day 7 compared to the untreated sample & & 0.76 & \(-\)2.19 & 0.17 & \(-\)5.40 \\ \hline Covington & on day 5 compared to day 0 & 24.68 & 27.80 & 25.03 & 23.11 & 22.55 \\  & on day 5 compared to the untreated sample & & 23.01 & 22.30 & 27.62 & 25.61 \\ \hline \end{tabular}
\end{table} 
Table 5: Results of the \(\Delta\)E* and the browning index (BI) of treated Covington (dark orange) and Bonita (white) varieties of sweet potatoes after storage. It has been established that a wide variety of Gram-positive bacteria, most notably LAB, is associated with the spoilage of fresh-cut fruits and vegetables that are packaged under a modified atmosphere and stored at a lower temperature. The process of lactic acid bacterial fermentation results in a decrease in pH, a consequence of the production of lactic acid. In addition, the fermentation process gives rise to the production of acetyl methylcarboni and diacetyl, which are responsible for an undesirable flavour reminiscent of buttermilk. It is noted that other fermentation products such as acetic acid, ethanol, formic acid, and CO\({}_{2}\) are also produced. LAB were detected in almost every fresh-cut product [24]. As demonstrated by [PERSON] et al. in 1996 [49], a significant increase (log\({}_{10}\) 5-6) in the number of LAB was detected in the analysed product after storage at low temperatures in a vacuum. This indicates that spoilage can be induced by LAB in environments devoid of oxygen. In the work by [PERSON] et al. [29], a comparative analysis was conducted on the effects of vacuum packaging and modified atmosphere packaging (MAP) on fresh-cut potatoes. Their study revealed that vacuum packaging resulted in higher germ counts during storage at 4 \({}^{\circ}\)C when compared to MAP, which indicates that the application of vacuum packaging by itself is inadequate to extend the shelf life of fresh-cut potatoes, even when stored at low temperatures. It is therefore reasonable to combine vacuum packaging and low-temperature storage with other antimicrobial effects in order to increase the shelf life of fresh products. An investigation was conducted by [PERSON] and [PERSON] in 1987 [50] to ascertain the impact of vacuum packaging on the microbial spoilage of ready-to-use carrot slices and the shelf life of the product. The microbial development on vacuum-packaged carrots was found to be slower than that of the non-vacuum-packaged material. The predominant organisms present were _Leuconostoc_ spp. in the vacuum packs, as opposed to _Erwinia_ spp. in the aerobic ones.