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''Brettanomyces'' is able to ferment a wide range of sugars. All strains can ferment glucose, and many strains can ferment sucrose, fructose, and maltose, although at a slower rate than glucose. The ability of ''Brettanomyces'' to produce invertase enzyme which breaks sucrose down into glucose and fructose has been attributed to horizontal gene transfer from an unknown bacteria at some point in the evolution of ''Brettanomyces'' <ref name="roach_2019">[https://www.biorxiv.org/content/10.1101/805721v2 New genome assemblies reveal patterns of domestication and adaptation across Brettanomyces (Dekkera) species. Michael J. Roach, Anthony R. Borneman. 2019. DOI: https://doi.org/10.1101/805721.]</ref>. Some strains can also ferment galactose, mannose, ethanol, acetic acid, malic acid, and glycerol, although historically there are some contradicting studies in science regarding the specifics (more recent studies tend to use better methods), probably due to the genetic diversity of ''Brettanomyces'' species, and many previously published studies do not specify whether testing conditions were aerobic or anaerobic even though the availability of oxygen effects whether or not certain sugars can be fermented by a given strain of ''Brettanomyces'' <ref name="Steensels"></ref><ref name="smith_divol_2016"></ref><ref name="Smith_2018" />. For example, the species ''B. naardenensis'' can ferment a wide range of carbon sources, including galactose, maltose, xylose, trehalose, cellobiose, rhamnose, and arabinose <ref name="Tiukova_2019" />. Acetic acid, glycerol, succinic acid, and ethanol are only consumed if oxygen is present <ref name="smith_divol_2016"></ref>. The addition of H+ acceptors such as acetaldehyde, acetone, pyruvic acid, and other carbonyl compounds, stimulates anaerobic fermentation. Small amounts of oxygen also stimulate fermentation <ref name="yakobson_introduction">[http://www.brettanomycesproject.com/dissertation/introduction/ Yakobson, Chad. The Brettanomyces Project. Introduction. Retrieved 8/11/2015.]</ref>. The presence of small amounts of oxygen can allow some strains of ''Brettanomyces'' to utilize certain carbon sources. For example, several strains of ''B. bruxellensis'' can consume ethanol, glycerol, and acetic acid as food sources only when at least a low amount of oxygen is present (semi-aerobic conditions) and no other sugar is available. Acetic acid and glycerol are used as food sources by some strains only under fully aerobic conditions, but not under semi-aerobic or anaerobic conditions. It has been hypothesized that acetic acid and glycerol are only consumed by ''Brettanomyces'' when ethanol and other food sources are no longer available <ref name="Smith_2018" />.