The research investigated the accumulation of malic acid and diacetyl in the white wines during the alcoholic fermentation of must with a Saccharomyces cerevisiae wine yeasts isolated by the author and Oenococcus oeni malolactic bacteria in a concentration of 10⁶ CFU/mL. The two aroma compounds were detected and quantified in the resulting wines, making a comparison between the two technological systems, i.e.: co-inoculation of malolactic bacteria and sequential inoculation. Based on our determinations, it was ascertained that the Oenococcus oeni malolactic bacteria co-inoculation system in fermentative processes leads to a substantial reduction of malolactic bacteria and diacetyl concentrations. Thus, harmonious, balanced white wines are obtained, as specific to the area.