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added info about impacts of temperature on carbohydrate fermentation
===Carbohydrate Metabolism===
''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. Some strains can also ferment galactose, mannose, ethanol, acetic acid, and glycerol, although there are some contradicting studies in science regarding the specifics, and many previously published studies do not specify whether testing conditions were aerobic or anaerobic even though the available 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>. Acetic acid, glycerol, succinic acid, and ethanol are only consumed if oxygen is present <ref name="smith_divol_2016"></ref>.
''Brettanomyces'' strains may possess both alpha and beta glucosidases. These enzymes allow ''Brettanomyces'' strains to break down a broad range of sugars, including longer chain carbohydrate molecules (polysaccharides, dextrins, and cellulose/cellobiose), and to liberate glycosidically bound sugars which are unfermentable to ''Saccharomyces'' yeasts. <ref name="Steensels"></ref><ref>[http://www.scribd.com/doc/277758178/Insight-into-the-Dekkera-anomala-YV396-genome Insight into the Dekkera anomala YV396 genome. Samuel Aeschlimann. Self published on Eureka Brewing Blog. Spet 2015.]</ref>.
The ability of a given ''Brettanomyces'' strain to ferment different types of sugars might be at least partially linked to its source of isolation. For example, a strain of ''B. bruxellensis'' isolated from a soft drink could not ferment the disaccharides maltose, turanose, or the trisaccharide melezitose, whereas all of the other ''B. bruxellensis'' strains isolated from beer and wine could ferment these disaccharides/trisaccharide. The beer strains, however, were unable to ferment cellobiose or gentiobiose, as well as arbutin and methyl-glucoside. The wine strains were able to ferment these disaccharides, perhaps because they were adapted to the environment in which they were isolated from (wine barrels). Further studies are needed to see if this is a trend throughout the species <ref name="Crauwels1"></ref>.
Currently, research into how well ''Brettanomyces'' strains ferment the trisaccharide maltotriose has not been explored much by science, however one study found that ''B. custersianus'' can ferment maltotriose. Another study found that all 7 strains of ''B. bruxellensis'' tested could ferment maltotriose, but not the trisaccharide raffinose. More investigation into this possibility is needed <ref>[http://www.asbcnet.org/events/archives/2015Meeting/proceedings/Pages/54.aspx Determination of sugar metabolism profiles of non-traditional yeasts in the Saccharomyces and Brettanomyces families. J. D. Cook, W. A. DEUTSCHMAN. ASBC Proceeding. 2015.]</ref><ref name="Crauwels1"></ref>. Just like in other yeast species, temperature has a direct effect on the rate of fermentation for ''Brettanomyces''. The optimal fermentation rate temperature range for ''Brettanomyces'' is between 25-32°C (77-90°F). Fermentation rate is about half as slow at 20°C (68°F). ''Brettanomyces'' will still grow at temperatures as low as (and maybe lower than) 15°C (59°F) and will be much slower, however one study showed a slightly higher viability during the full time period of fermentation at 15°C as opposed to the optimal growth and fermentation temperature range of 20-32°C. At a temperature of 35°C (95°F), fermentation is greatly inhibited due to cell death. The primary byproducts of ''Brettanomyces'' fermentation, which are ethanol, acetic acid, and CO2, are produced both during growth but also during fermentation after growth has stopped. At the more optimal fermentation temperatures of 25-32°C, ethanol and acetic acid are produced faster from fermentation, but the amounts of ethanol and acetic acid produced from fermentation are not affected by temperature (i.e. higher temperatures do not produce more ethanol and acetic acid from the same amount of sugar, they are just produced faster at warmer temperatures because fermentation is faster) <ref name="Brandam_2008" />.
The below table is an example of the variety of sugar types that different strains/species of ''Brettanomyces'' banked at the [https://catalogue.ncyc.co.uk National Collection of Yeast Cultures] can ferment under semi-aerobic fermentation and aerobic growth (the '''semi-aerobic''' fermentation value is probably more useful for brewers since oxygen availability is limited during fermentation in normal brewing practices):