The enzymatic degradation of lactose in whey by β-galactosidase makes it possible to intensify alcoholic fermentation through increasing the availability of sugars and the possibility of applying strains of non-lactose fermenting bacteria, which are traditionally used in the production of alcoholic beverages. The objective of the study was to evaluate the possibility of using BAYANUS G995 yeast (Spirit Ferm., Sweden) and to determine the dynamics of fermenting whey with a natural content of lactose and low-lactose whey. The paper presents the results of quality evaluation of whey beverages saturated with CO2. The alcoholic fermentation was performed at 23 ºC during a period of 28 days. Every 7 days, sucrose was added to the whey under fermentation. Once a week, there were monitored: content of saccharides, content of protein, pH value, total acidity, and, after the fermentation, content of alcohol. After 28 days, whey beverages were decanted, flavouring innards were added, and the beverages were sweetened using sucrose. The whey beverages were fermented at a temperature of 25 ºC during a period of 4 days to saturate them with carbon dioxide. Next, the beverages were chilled down to 5ºC and underwent sensory and physical-chemical analysis. Saccharomyces bayanus can be utilized in the production of carbonated beverages made from whey with a natural content of lactose and from low-lactose whey. After 28 days of fermentation, it was found that the content of alcohol in the low-lactose beverages was 1 % higher compared to that in the whey beverages with the natural content of lactose: 9.50 % and 8.50 %, respectively. During the 28 day fermentation period, the pH value of the whey fermented decreased by 0.5 unit (from a value of 4.56 to 4.06) whereas that of the low-lactose whey decreased by 0.45 unit (from a value of 4.50 to 4.05). During fermentation, a systematic increase was also recorded in total acidity of the whey with natural content of lactose (from 0.36 g/l (on 0 day of fermentation) to 0.67 g/l (on the 28th day of fermentation) as well as of the low-lactose whey (from 0.46 g/l (on 0 day of fermentation) to 0.69 g/l on the 28th day of fermentation). The beverages produced from the low-lactose whey were characterized by a better clarity, better colour, and by a more intense sweet flavour in comparison with the beverages made from whey with a natural content of lactose.