## 3 Results and Discussion  
### Microbiological Analyses and Survival of AAB Starter Culture in Beer Beverages  
Table 2 presents the changes in the total count of yeast, AAB, and pH values in the beer beverages after the re-fermentation process and after 6 months of storage. In this research variant of study beer beverages, significant changes in the number of AAB were found between 0 and after 6 months of storage (\(p<\) 0.05). These changes were also found between the light (BPGL) and dark (BPGD) types of the study beers. In this case, the count of AAB is related only to the survival of the starter culture _G. oxydans_ H32. In light beer, the number of AAB decreased by two logarithmic levels and was still high after 6 months of storage (approximately 6.39 log CFU mL\({}^{-1}\)). In dark beer, the total count of AAB decreased by as much as four logarithmic orders and was on average 4.20 log CFU mL\({}^{-1}\) at the end of the experiment. Statistical differences in the number of AAB between the samples of light beer with their addition (BGL--unpasteurized light beer inoculated with the studied starter culture _G. oxydans_ H32 and BPGL--pasteurized light beer inoculated with the studied starter culture _G. oxydans_ H32) were not observed before storage period (\(p>\) 0.05). After the re-fermentation process, the AAB count was approximately 8.04 log CFU mL\({}^{-1}\) and after 6 months of storage, the number of AAB decreased approximately by about three logarithmic levels in the BGL sample (\(p<\) 0,05). Significant differences (\(p<\) 0.05) of the total count of AAB were found also in the BGL variant of the studied beer between BPGL after storage time. In the sample, BPGL survived by 1.33 log CFU mL\({}^{-1}\) more bacteria than in the BGL sample, whereas there were no statistically significant changes in the number of AAB in the sample BGD of dark beer. The count of bacteria was on average at the level of 7 log CFU mL\({}^{-1}\) in the case of this sample (\(p>0.05\)). Based on these results, it can be concluded that the survival rate of _G. oxydans_ H32 differs depending on the presence of live yeast cells, raw materials used in production, and the beer variant. The survival of these bacteria was influenced by the presence of live yeasts and the type of beer (light/dark). Nevertheless, the high survival rate of _G. oxydans_ H32 bacteria was present in all types of beer. Compared to the studies by [PERSON] et al. [31], the number of bacteria added in our study remained at a similar level. However, in our research, the beer was stored 5 months longer than in the [PERSON] research. Compared to the research conducted by [PERSON] et al. [31], the number of added bacteria was similar to that in the presented studies after only 24 days. These results are suggestive of the high survival of AAB in beer despite the lack of access to oxygen. On the other hand, [PERSON] et al. [1] demonstrated that in an unpasteurized sample of craft beer, a combination of live Saccharomyces cerevisiae S-04 and low temperature significantly enhanced the survival of the probiotic lactic acid bacteria (LAB). According to [PERSON] et al. [13] and [PERSON] [32], other intrinsic chemical constituents in beer, including yeast, ethanol, and carbon dioxide may enhance probiotic viability and stability. Although, [PERSON] et al. [33] observed an enhancement in their probiotic survival in acidic environments such as fermented milk, possibly due to the formation of mixed-species biofilms which protect probiotic bacteria from external stress. The obtained results of the microbiological analyses were used in determining the total count of AAB and were carried out to confirm the survival ability of a novel starter culture of _G. oxydans_ H32 in the variants of beer beverages. _G. oxydans_ H32 was isolated from the natural microbiota of local Kombucha drink, identified and classified to the AAB group as safe for humans [19; 23]. Furthermore, H32 has been subjected to preliminary in vitro tests recommended by FAO/WHO [17]. Despite the fact that the _G.