''Lachancea thermotolerans'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...

Taxonomy

''L. thermotolerans'' is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

'' Lachancea''. The species has previously been known as ''Kluyveromyces thermotolerans'' and ''Zygosaccharomyces thermotolerans'', which is the name by which it was first described in 1932.

Habitat and ecology

''L. thermotolerans'' is widely distributed and occurs in diverse environments, both natural and man-made. It has been isolated from locations around the world. The species is commonly associated with fruit and with insects such as

fruit flies Fruit fly may refer to: Organisms * Drosophilidae, a family of small flies, including: ** ''Drosophila'', the genus of small fruit flies and vinegar flies ** ''Drosophila melanogaster'' or common fruit fly ** ''Drosophila suzukii'' or Asian fruit ...

that feed on fruit. In some cases, it has been identified as one of several species found in naturally fermented foods.

Uses

''L. thermotolerans'' is unusual among yeasts in its ability to produce

lactic acid Lactic acid is an organic acid. It has a molecular formula . It is white in the solid state and it is miscible with water. When in the dissolved state, it forms a colorless solution. Production includes both artificial synthesis as well as natu ...

through

fermentation Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen. In food ...

. This property has prompted study of ''L. thermotolerans'' in the production of

wine Wine is an alcoholic drink typically made from fermented grapes. Yeast consumes the sugar in the grapes and converts it to ethanol and carbon dioxide, releasing heat in the process. Different varieties of grapes and strains of yeasts are m ...

and

beer Beer is one of the oldest and the most widely consumed type of alcoholic drink in the world, and the third most popular drink overall after water and tea. It is produced by the brewing and fermentation of starches, mainly derived from ce ...

, both of which are traditionally produced using ''

Saccharomyces ''Saccharomyces'' is a genus of fungi that includes many species of yeasts. ''Saccharomyces'' is from Greek σάκχαρον (sugar) and μύκης (fungus) and means ''sugar fungus''. Many members of this genus are considered very important in f ...

'' yeasts. In

winemaking Winemaking or vinification is the production of wine, starting with the selection of the fruit, its fermentation into alcohol, and the bottling of the finished liquid. The history of wine-making stretches over millennia. The science of wine and ...

, ''L. thermotolerans'' and other yeast species have been studied for the effects of their

metabolite In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...

s on the flavor profile of wines. Systems including ''L. thermotolerans'' in co-fermentation with wine yeast or in place of

lactic acid bacteria Lactobacillales are an order of gram-positive, low-GC, acid-tolerant, generally nonsporulating, nonrespiring, either rod-shaped (bacilli) or spherical (cocci) bacteria that share common metabolic and physiological characteristics. These bacte ...

have been described as an alternative to traditional

malolactic fermentation Malolactic conversion (also known as malolactic fermentation or MLF) is a process in winemaking in which tart-tasting malic acid, naturally present in grape must, is converted to softer-tasting lactic acid. Malolactic fermentation is most often p ...

. ''L. thermotolerans'' has been sold commercially on its own and in a yeast blend. In

beer brewing Brewing is the production of beer by steeping a starch source (commonly cereal grains, the most popular of which is barley) in water and fermenting the resulting sweet liquid with yeast. It may be done in a brewery by a commercial brewer ...

, ''L. thermotolerans'' has been considered as a method for producing

sour beer Sour beer, also known as Sours, is beer which has an intentionally acidic, tart, or sour taste. Traditional sour beer styles include Belgian lambics, gueuze and Flanders red ale, and German gose and Berliner Weisse. Brewing Unlike modern brewing, ...

. It has been observed that this kind of yeast ferments at low temperatures (17 °C) as well as at high temperatures (27 °C) and with SO2 doses of 25 mg/L and 75 mg/L with an ethanol yield between 7-11% vol. Sequential inoculations (binary) and sequential co-inoculations (ternary) with different non-Saccharomyces, including L. thermotolerans, have also been studied, resulting in very significant synergies and inhibitions in lactic acid production.

References

{{Taxonbar, from=Q10552620 Yeasts Fungi described in 2003 Wine chemistry Yeasts used in brewing