fermentation
Review
Novel Non-Cerevisiae Saccharomyces Yeast Species
Used in Beer and Alcoholic Beverage Fermentations
James Bruner * and Glen Fox *
Food Science and Technology, University of California, Davis, CA 95616, USA
* Correspondence: [email protected] (J.B.); [email protected] (G.F.)
Received: 28 October 2020; Accepted: 22 November 2020; Published: 24 November 2020

 
Abstract:
A great deal of research in the alcoholic beverage industry was done on non-Saccharomyces
yeast strains in recent years. The increase in research interest could be attributed to the changing of
consumer tastes and the search for new beer sensory experiences, as well as the rise in popularity
of mixed-fermentation beers. The search for unique flavors and aromas, such as the higher
alcohols and esters, polyfunctional thiols, lactones and furanones, and terpenoids that produce
fruity and floral notes led to the use of non-cerevisiae Saccharomyces species in the fermentation process.
Additionally, a desire to invoke new technologies and techniques for making alcoholic beverages
also led to the use of new and novel yeast species. Among them, one of the most widely used
non-cerevisiae strains is S. pastorianus, which was used in the production of lager beer for centuries.
The goal of this review is to focus on some of the more distinct species, such as those species of
Saccharomyces sensu stricto yeasts: S. kudriavzevii, S. paradoxus, S. mikatae, S. uvarum, and S. bayanus.
In addition, this review discusses other Saccharomyces spp. that were used in alcoholic fermentation.
Most importantly, the factors professional brewers might consider when selecting a strain of yeast for
fermentation, are reviewed herein. The factors include the metabolism and fermentation potential of
carbon sources, attenuation, flavor profile of fermented beverage, flocculation, optimal temperature
range of fermentation, and commercial availability of each species. While there is a great deal
of research regarding the use of some of these species on a laboratory scale wine fermentation,
much work remains for their commercial use and efficacy for the production of beer.
Keywords: yeast; Saccharomyces; fermentation; alcohol; beer; wine
1. Introduction
Fermented beverages have played an important and special role over the course of human
history due to their economic and cultural importance, perhaps even lending to the beginning of
modern civilizations [
1
,
2
]. Archaeological evidence places the oldest fermented beverage in the fertile
crescent, as far back as 11,000 BCE [
3
,
4
], and based on the agricultural evidence of the time and
region, that beverage was likely beer. While beer originally could have been an accidental beverage,
it progressed into one of the most artfully crafted beverages known to man. No longer thought of as
just an art, the science of beer led to several very important landmarks in scientific history (Table 1).
As scientific discoveries keep developing, there are some amazing innovations that led to advances in
the quality and stability of beer, over the past 40 years [
5
]. However, minimal advancement was made
when considering the raw ingredients used in the brewing process.
Fermentation 2020, 6, 116; doi:10.3390/fermentation6040116 www.mdpi.com/journal/fermentation
Fermentation 2020, 6, 116 2 of 16
Table 1.
Significant landmarks of the 150 years from 1760–1910 that came from scientists working at
breweries or specifically studying beer and its adjacent ingredients.
Year Scientist Employment Discovery
1762 Michael Combrune
Brewer’s Company
Middlesex
using a thermometer for analysis [2]
1769 James Baverstock family brewery using a hydrometer for analysis [2]
1833
Anselme Payen and
Jean-François Perzoz
École Centrale Paris
discovered diastase enzyme and cellulose while
working with barley [2]
1843 Karl J.N. Balling Polytechnic in Prague invents the balling saccharimeter [6]
1843
James Joule and
Lord Kelvin
family brewery
create temperature scale and first law of
thermodynamics [7]
1857 Louis Pasteur University of Lille microbes are responsible for fermentation [8]
1860 P.E. Marcellin Berthelot Collège de France discovered invertase in Saccharomyces [2]
1873 Carl von Linde Spaten Brewery invented the refrigeration cycle [2]
1883 Johan Kjeldahl Carlsberg Brewery develops method for protein quantification [9]
1888 Emil Christian Hansen Carlsberg Brewery first isolation of pure yeast strain [9]
1908 William Sealy Gosset Guinness Brewery invents the statistical t-test for students [10]
1909 Søren Sørenson Carlsberg Brewery
creates pH scale based on H
+
ion concentration [
11
]
On a base level, beer consists of four main ingredients—malt, water, hops, and yeast, and the
brewing process could be separated into a hot side and a cold side. In the most basic overview of
the brewing process, the hot side begins when malted cereal grains are crushed and combined with
warm water so the maltose sugar is hydrolyzed from starch, the liquid is then boiled with hops to
add bitterness and flavor; this liquid, called wort, provides the nutrients for yeast. Moving from the
hot side to the cold side, wort is subsequently chilled for fermentation (Figure 1a); yeast is added,
metabolizing 50 to 80 percent of the sugar and nutrients to fermentation products, leaving behind non
metabolized proteins, oligosaccharides, and other compounds [
12
–
14
]. The resultant sugar profile of
brews can vary, based on the malting and mashing conditions, but typical mashes might contain 60.0%
maltose, 20.0% glucose, 10.0% maltotriose, and 5.0% of both sucrose and fructose [15].
Conversely, wine has just two main ingredients, grapes and yeast, and tends to have a much
simpler process flow than beer (Figure 1b). Grapes are picked and sorted from the vineyard before
being crushed, to release the sugary juice from the interior, for the varying fermentation profiles of
red or white wine. When producing white wine the skins and pomace are pressed and filtered from
the juice before the addition of yeast for fermentation. While red wine is fermented on the pomace to
get the color from the polyphenols within the skins and seeds, before being pressed and filtered for
aging. Wine might also have an additional malolactic fermentation to soften the malic acid into lactic
acid, but the lactic acid bacteria can produce a buttery diacetyl flavor that is only desirable in certain
styles [
16
]. In wine, the resultant sugar profile can vary, based on that of the grapes used, but the
majority (~95.0%) of sugars are already present in monosaccharide form, as equal parts glucose and
fructose, which the yeast can ferment without the assistance of enzymes [17,18].
For most of the scientific history of beer, Saccharomyces cerevisiae was the yeast used to produce
alcohol [
19
–
21
] although the first pure culture isolate of brewing yeast was S. carlsbergensis (later renamed
S. pastorianus) [
22
]. For alcoholic fermentation, the general rule of thumb for the amount of yeast to use,
known as the pitching rate, is one million cells per milliliter per percent of sugar in solution [
9
,
12
,
23
].
S. cerevisiae, when used at the proper pitching rate, takes the maltose and other sugars produced
from the hot side of the brewing process [
15
], and anaerobically converts the disaccharides into
carbon dioxide (CO
2
) and ethanol. More than 600 flavor active compounds can also be produced
during the alcoholic fermentation process, depending on type of beverage produced (Figure 2) [
24
–
26
].
Yeast works via an anaerobic pathway of glycolysis; if oxygen is present it performs respiration and
cell reproduction [27].
Fermentation 2020, 6, 116 3 of 16
Fermentation 2020, 6, x FOR PEER REVIEW 3 of 17
On a base level, beer consists of four main ingredients—malt, water, hops, and yeast, and the
brewing process could be separated into a hot side and a cold side. In the most basic overview of the
brewing process, the hot side begins when malted cereal grains are crushed and combined with warm
water so the maltose sugar is hydrolyzed from starch, the liquid is then boiled with hops to add
bitterness and flavor; this liquid, called wort, provides the nutrients for yeast. Moving from the hot
side to the cold side, wort is subsequently chilled for fermentation (Figure 1a); yeast is added,
metabolizing 50 to 80 percent of the sugar and nutrients to fermentation products, leaving behind
non metabolized proteins, oligosaccharides, and other compounds [12–14]. The resultant sugar
profile of brews can vary, based on the malting and mashing conditions, but typical mashes might
contain 60.0% maltose, 20.0% glucose, 10.0% maltotriose, and 5.0% of both sucrose and fructose [15].
(a)
(b)
Figure 1. (a) Schematic diagram of the brewing process, as presented in Magalhães et al. 2009 [14].
(b). Schematic diagram of the winemaking process as outlined and described by Water house et al.
2016 [16].
Figure 1.
(
a
) Schematic diagram of the brewing process, as presented in Magalh
ã
es et al. 2009 [
14
].
(
b
). Schematic diagram of the winemaking process as outlined and described by Water house et al.
2016 [16].
In Stage 1 of alcoholic fermentation, free glucose is assimilated first, followed by the hydrolyzation
of maltose or other disaccharides into two glucose, by the enzyme alpha glucosidase (a.k.a maltase,
EC 3.2.1.20). Several other enzymatic destabilization and phosphorylation reactions then happen
in Stage 1, which turns the substrate into glyceraldehyde-3-phosphate (G3P) and dihydroxyacetone
phosphate (DHAP). Stage 2 oxidizes G3P and DHAP, as well as the ADP generated previously,
to create ATP as energy for the cell and pyruvate. Stage 3 enzymatically decarboxylates pyruvate to
acetaldehyde and CO
2
that leaves the cell, before the alcohol dehydrogenase converts the acetaldehyde
to ethanol in Stage 4 (Figure 2). In brewing, yeast is typically reused (repitched) for ten generations or
more [
9
], while in wine, the yeast is generally used far lesser times, due to the prominence of other
microorganisms and the higher mortality from more stressful conditions of osmotic pressure and
higher ethanol concentrations [
28
]. In most cases, serial repitching can cause genetic mutation within
the cells and the desired flavor profile might no longer be attainable [29–32].
Fermentation 2020, 6, 116 4 of 16
Fermentation 2020, 6, x FOR PEER REVIEW 4 of 17
Conversely, wine has just two main ingredients, grapes and yeast, and tends to have a much
simpler process flow than beer (Figure 1b). Grapes are picked and sorted from the vineyard before
being crushed, to release the sugary juice from the interior, for the varying fermentation profiles of
red or white wine. When producing white wine the skins and pomace are pressed and filtered from
the juice before the addition of yeast for fermentation. While red wine is fermented on the pomace to
get the color from the polyphenols within the skins and seeds, before being pressed and filtered for
aging. Wine might also have an additional malolactic fermentation to soften the malic acid into lactic
acid, but the lactic acid bacteria can produce a buttery diacetyl flavor that is only desirable in certain
styles [16]. In wine, the resultant sugar profile can vary, based on that of the grapes used, but the
majority (~95.0%) of sugars are already present in monosaccharide form, as equal parts glucose and
fructose, which the yeast can ferment without the assistance of enzymes [17,18].
For most of the scientific history of beer, Saccharomyces cerevisiae was the yeast used to produce
alcohol [19–21] although the first pure culture isolate of brewing yeast was S. carlsbergensis (later
renamed S. pastorianus) [22]. For alcoholic fermentation, the general rule of thumb for the amount of
yeast to use, known as the pitching rate, is one million cells per milliliter per percent of sugar in
solution [9,12,23]. S. cerevisiae, when used at the proper pitching rate, takes the maltose and other
sugars produced from the hot side of the brewing process [15], and anaerobically converts the
disaccharides into carbon dioxide (CO
2
) and ethanol. More than 600 flavor active compounds can
also be produced during the alcoholic fermentation process, depending on type of beverage
produced (Figure 2) [24–26]. Yeast works via an anaerobic pathway of glycolysis; if oxygen is present
it performs respiration and cell reproduction [27].
Figure 2. The metabolic role of Saccharomyces yeast in the development of flavor for fermented
alcoholic beverages. The sole products of yeast fermentation are not just ethanol and CO
2
, this
schematic representation shows the derivation and synthesis of flavor active compounds from sugar,
amino acids, and sulfur metabolism, delineated by the arrows on the diagram. Alcoholic fermentation
of beer by Saccharomyces is the substrate level phosphorylation anaerobic pathway of glycolysis,
which converts maltose sugar into ethanol and carbon dioxide.
In Stage 1 of alcoholic fermentation, free glucose is assimilated first, followed by the
hydrolyzation of maltose or other disaccharides into two glucose, by the enzyme alpha glucosidase
(a.k.a maltase, EC 3.2.1.20). Several other enzymatic destabilization and phosphorylation reactions
then happen in Stage 1, which turns the substrate into glyceraldehyde-3-phosphate (G3P) and
dihydroxyacetone phosphate (DHAP). Stage 2 oxidizes G3P and DHAP, as well as the ADP
generated previously, to create ATP as energy for the cell and pyruvate. Stage 3 enzymatically
decarboxylates pyruvate to acetaldehyde and CO
2
that leaves the cell, before the alcohol
Figure 2.
The metabolic role of Saccharomyces yeast in the development of flavor for fermented alcoholic
beverages. The sole products of yeast fermentation are not just ethanol and CO
2
, this schematic
representation shows the derivation and synthesis of flavor active compounds from sugar, amino acids,
and sulfur metabolism, delineated by the arrows on the diagram. Alcoholic fermentation of beer by
Saccharomyces is the substrate level phosphorylation anaerobic pathway of glycolysis, which converts
maltose sugar into ethanol and carbon dioxide.
Interest in brewing beer with novel yeast strains and applying Saccharomyces cerevisiae in new
methods outside of traditional beer fermentation [
33
,
34
] has increased in recent years, due to the
growing consumer tastes of sour and wild mixed-fermentation beers, as well as using some of these
novel species for low or no alcohol beer production [
35
,
36
]. A great deal of research in the brewing
industry was done on non-Saccharomyces yeast strains, such as Brettanomyces, Pichia, Hanseniaspora,
Metschnikowia, and Torulaspora [
37
–
39
]. Furthermore, the search for unique flavors and aromas, and a
desire to invoke new technologies and techniques for making alcoholic beverages led to the use of
non-cerevisiae Saccharomyces spp. in the alcoholic fermentation process [40,41].
While the most widely used non-cerevisiae species is S. pastorianus, traditionally used in the
production of lager beer around the world [
42
–
44
], this review focuses on some of the more distinct
species. The focus is on five species of Saccharomyces sensu stricto (Sss) yeasts, S. kudriavzevii, S. paradoxus,
S. mikatae, S. uvarum, and S. bayanus, as well as other novel species not currently in the Sss, such as
S. abulensis and S. florentinus. When selecting yeast strains for fermentation, brewers consider
its attenuation (the amount of sugar consumed by the yeast), flocculation (the yeast’s ability to
clump together and fall out of solution), fermentation temperature range, effects on flavor profile,
capacity for reuse, and supply chain availability [
45
]. These facets, as well as a yeast’s ability to ferment
various carbon sources, morphological characteristics, and genetic hybridization can all assist brewers,
when adopting a new strain.
2. Saccharomyces Species Diversity
Since Louis Pasteur’s groundbreaking and historic report that fermentation was caused by a
microorganism instead of a spontaneous mystery [
8
], the Saccharomyces genome was continuously
studied, with several distinct species identified [
46
]. This diversity was termed the Saccharomyces sensu
stricto (Sss) complex and is currently composed of ten genetically distinct species, all of which are
capable of metabolizing glucose to produce ethanol (Figure 3). Each of these species was perceptibly
delineated from other Saccharomyces species, through studies of reproductive isolation and application
of the biological species concept [
31
,
47
–
49
]. All Sss species were isolated from unique sources in nature,
Fermentation 2020, 6, 116 5 of 16
including tree bark, flowers, fruit, and insects, demonstrating their lineage from wild type to the
cultured stock of Saccharomyces spp. While all members of the Sss were proven to produce energy with
fermentation, and many of these species are novel, some were used and studied for their potential
use in commercial alcohol production for human consumption. The distribution of S. cerevisiae and
S. pastorianus were long linked to alcoholic beverage production, along with minor mentions of other
species in the Sss complex. Cultured species, specific to beer production, were shown to have evolved
from European wine and Asian sake fermentations [
21
,
50
], therefore, its relation to wine production
proliferates much of the research.
Figure 3.
Saccharomyces species phylogeny shown; all were effectively isolated from natural sources
(i.e., trees, fruit, insects). Saccharomyces bayanus is listed in parenthesis to indicate it was derived from
multiple hybridization events. S. pastorianus is shown as a genetic hybrid of S. eubayanus and S. cerevisiae.
Usage indicated with plus signs (
+
) for current use in industry, with S. cerevisiae and S. pastorianus
showing the most profound use in the current alcoholic fermentation industry, and negative signs (
−
)
for no known use. S. cariocanus is known to be harboring just four translocated chromosomes different
than S. paradoxus. Figure adapted from Fay 2012 [51].
3. Saccharomyces kudriavzevii
S. kudriavzevii was first isolated from a decaying leaf and has since been isolated repeatedly
from the bark of oak trees in Portugal and France [
52
,
53
]. The yeast is a multipolar budding species,
with a size of 5–10
µ
m, and an oval to slightly elongated shape [
47
]. It was shown to ferment
glucose, sucrose, and maltose, but it did not ferment lactose, melibiose, or starch, which are common
characteristics of Sss yeast (Table 2). S. kudriavzevii is a naturally occurring S. cerevisiae hybrid that
might constitute 23–100% of the genome for some yeast [
54
,
55
], including Belgian trappist ale strains,
such as Chimay, Westmalle, and Orval, and wass also genetically isolated in draft beer from the United
Kingdom, Germany, and New Zealand [
56
]. This implies that the attenuation, flocculation, and flavor
profiles of S. kudriavzevii might be similar to that of most Belgian strains. This meant low flocculation,
high attenuation, and phenolic off-flavor positive (POF+) [
45
,
57
], though there is research in the wine
industry that suggests S. kudriavzevii ferments slowly and produces less ethanol when used on grape
juice [58]. Other research suggests it has high flocculation, as in overnight liquid culture, it grew into
spherical 2–3 mm pellets [31].
Fermentation 2020, 6, 116 6 of 16
Table 2.
Physiological characteristics that distinguish each species of the Saccharomyces sensu stricto
complex are discussed. Growth ability scored as positive (+), negative (
−
), evidence of both positive
and negative (
−
,+), and unknown (u). Ethanol tolerance is defined as being able to grow in the presence
of 2.5% v/v EtOH, the low-end strength of standard beer. Attenuation and flocculation scored on
a relative basis scale, ranging from low, to moderate, to high. Type strain as defined in MycoBank
(mycobank.org), origin, isolation, and commercial availability, as defined in the cited literature.
S. kudriavzevii S. paradoxus S. uvarum S. mikatae S. bayanus
Fermentation Of:
Maltose + + + + +
Melibiose − − + + −,+
Dextrins (STA1) −,+ − −,+ − −
Ethanol Tolerant + + + + +
Characteristics:
Attenuation moderate low-moderate moderate moderate moderate
Flocculation moderate-high moderate high moderate moderate
Growth at 10
◦
C + + + + +
Growth at 25
◦
C + + + + +
Growth at 37
◦
C − − + − +
POF + u − u +
Region of Origin Western Europe
Northeastern Europe
Scandinavia Japan Europe
Isolated From Oak tree bark Oak sap Fruit/Seeds Soil/Leaves Insects/Leaves
Type Strain NCYC 2889T DBVPG 6411 DBVPG 6173 NCYC 2888T CBS 380
CommercialAvailability Anchor Vin7 Anchor Exotics SPH AWRI 1176 & 1375 AB Biotek/AWRI 2526 Lalvin S6U
It is advised to ferment S. kudriavzevii in tandem with a traditional Saccharomyces [
59
] and it was
shown to form a triple hybrid complex with S. cerevisiae and S. uvarum, as it was isolated as such from
farmhouse ciders made in France [
60
,
61
]. S. kudriavzevii is a cryophilic strain in the Sss that prefers
fermentation temperatures in the 10–15
◦
C range [
52
,
62
,
63
], and is currently used to ferment lower
temperature pinot noir and lager beer in Europe [
54
]. The only current commercially available example
is Anchor Oenology’s Vin7 strain, developed in Stellenbosch, South Africa, for enhancing thiol aromas
in white wine [
64
,
65
], but it stands to reason that it can be isolated from previously noted commercial
beer examples. Due to its cryophilic tendencies and aromatic potential, S. kudriavzevii has potential for
use in the production of hoppy lager beers in the brewing industry. Further research remains to be
done on this species, considering it is POF+ and it is likely also diastaticus (STA1) positive, meaning it
could ferment residual maltodextrins. Additionally, minimal commercial production was done with
the direct intention of using S. kudriavzevii, as most fermentations did not take place with the intention
of the use of this species.
4. Saccharomyces paradoxus
S. paradoxus is one of the first isolates of the Sss [
66
], a wild-type strain commonly isolated from
the bark of deciduous trees and occasionally from fruit and insects in North America and Eastern
Europe [
67
–
69
]. Even though genetically S. cerevisiae and S. paradoxus were proven to be distinct
species [
70
], phylogenetically the two were the closest relatives in the Sss (Figure 3) and were 90%
genetically similar [
55
]. They share the same morphological and phenotypic characteristics, such as
being spherical or ellipsoid in shape, with a diameter of 1–5
µ
m [
71
]. Previous research indicates
mixed results of the fermentative capacity of S. paradoxus, but it has the ability to convert glucose
into ethanol and a relatively high alcohol tolerance [
47
,
72
,
73
]. It is a positive fermenter for glucose,
sucrose, and maltose, but it does not ferment lactose, melibiose, or starch (Table 2). Little evidence
exists for the domestication and commercial use of S. paradoxus in alcohol fermentation, but it was
found to be naturally co-fermenting with S. cerevisiae in Eastern European wine fermentations [
73
,
74
],
as well as with S. cerevisiae, S. bayanus, S. cariocanus, S. kudriavzevii, S. mikatae, and S. pastorianus in
indigenous African sorghum beer [75].
In laboratory fermentations, the optimal growth temperature for S. paradoxus falls 7
◦
C lower
than S. cerevisiae, and is likely cryophilic, due to the climates in which it is found, but S. paradoxus
is yet to be trialed extensively in a production environment [
76
,
77
]. Unfortunately, no information
Fermentation 2020, 6, 116 7 of 16
exists on the attenuation or flocculation characteristics of S. paradoxus, nor are there any commercially
produced examples of the purely isolated species, but it does seem to have positive sensory attributes
in white wine fermentations [
73
,
74
]. There is a commercially available hybrid of S. paradoxus and
S. cerevisiae produced by Anchor Oenology, which when used for Syrah and Merlot wine fermentations,
shows increased aromas of cherries, strawberries, cocoa, and floral notes, and the wine is described as
full-bodied, well-balanced, complex and intense [
78
]. Much work remains to be done on the versatility
of this species for the brewing industry, but it might have potential for unique and novel flavor
characteristics if a pure culture from a genetic bank is obtained for further experimentation.
5. Saccharomyces mikatae
S. mikatae is a natural genetic hybrid that results from introgression events with S. cerevisiae and
S. paradoxus [
55
,
79
], and its current hybrids are described for use in industrial wine fermentation.
This hybrid was deliberate, created in a lab with the intent of creating greater complexity in resultant
wines, akin to those that are spontaneously fermented, but more easily controlled due to the inclusion
of typical S. cerevisiae yeast [
80
,
81
] S. mikatae was first isolated from decaying leaves and soil in
Japan [
47
,
60
]. It is ovoid in shape and approximately 5–9
µ
m in diameter; it reproduces by multipolar
budding, and generally appears in pairs or short chains. S. mikatae was also shown to form a pellicle
after 25 days at 20
◦
C, similar to Brettanomyces and other wild-type yeasts [
47
]. The inclusion of S. mikatae
in the Sss means it is capable of alcoholic fermentation and assimilation of glucose, it is also capable of
fermenting maltose, sucrose, and melibiose, but not lactose or starch (Table 2). However, S. mikatae
might have a lower attenuation, due to genetic diversion from S. cerevisiae, while still exhibiting similar
levels of flocculence [31].
S. mikatae readily creates hybrids with S. cerevisiae, and these hybrids were shown to produce
higher concentrations of multiple compounds that yield fruity, banana, floral, and sweet perfume
aromas in the fermentation of white wine [
80
,
81
]. Although no information on beer fermentation with
either the type strain or any hybrids exist, the additional amounts of certain volatile compounds in the
research by Bellon et al. (2013, 2019) might show signs of this yeast’s production of phenolic off flavors.
S. mikatae grows readily in temperatures from 4–30
◦
C, with expected slower growth in the range limits
and no growth outside the range, making it a cryotolerant fermenter [
47
,
63
]. Commercial availability
is limited, but yeast manufacturer AB Biotek commenced exploratory production of an S. mikatae and
S. cerevisiae hybrid, AWRI 2526; brewers and winemakers can expect the hybrid as an active dried yeast
product that is expected to be available for trials, by the fall of 2020 [81].
6. Saccharomyces uvarum
S. uvarum is a fairly well-known member of the Sss, originally believed to be identical to
S. bayanus and often referred to as S. bayanus var. uvarum, it was shown to be a genetically
distinct Saccharomyces species [
82
–
84
]. S. uvarum is also similar in size and shape to S. bayanus,
being spherical or ellipsoid in shape, with a diameter of 1–5
µ
m, and reproducing by multipolar
budding. S. uvarum was isolated in natural European wine and cider fermentations [
85
–
87
], as well
as in South American chicha fermentations [
88
,
89
], but was first isolated in 1894 and described in
1898 by M.W. Beijerinck, from spontaneous wine fermentation [
90
]. S. uvarum is known to hybridize
with S. cerevisiae, S. bayanus, and S. pastorianus [
85
,
91
,
92
], and thus can show signs of being POF+
and possibly might have the STA1 gene for diastaticus [
91
,
93
]. S. uvarum showed the capacity to
ferment glucose, sucrose, melibiose, and maltose, but it does not ferment lactose. S. uvarum is a known
bottom-fermenting yeast, meaning it acts similar to a S. bayanus or S. pastorianus when not in hybrid
form, offering cryotolerance [94], moderate attenuation, and high flocculation (Table 2).
Research with wine showed that S. uvarum produces comparatively higher amounts
of volatile aromatics when fermented cold [
95
], implying potential use as a lager strain.
In Chardonnay winemaking trials, wines were described as showing apricot, cooked orange peel,
citrus, lime, honey, and nutty aromas with some tasters, and estery, pineapple, peach, melon, and floral
Fermentation 2020, 6, 116 8 of 16
aromas with others [
80
,
96
]. While S. uvarum continues to predominate in spontaneous European
wine fermentations [
86
,
87
,
97
] and is a known species in some Norwegian kveik hybrid strains [
91
],
its commercial availability is limited to the Australian Wine Research Institute at this time [
98
].
Cryotolerance and increased aromatic potential means S. uvarum could be used in the production of
some complex and eccentric lagers in the brewing industry, but currently, it has only been isolated as
part of a hybrid culture in the aforementioned kveik beer. Further research remains to be done on the
brewing potential of S. uvarum, but brewers should be aware of the increased aromatic character that
might come from the POF+ genes.
7. Saccharomyces bayanus
S. bayanus is a well-studied species in the Sss and is often used as a model organism for comparative
functional genomics studies of yeast, based on introgression and interspecific hybridization [
99
]. It is
genetically similar to S. cerevisiae, but evolved to be a distinct member of the Saccharomyces sensu
stricto complex [
55
,
100
], and is now referred to as S. bayanus var. bayanus, in order to delineate it
from S. eubayanus and S. uvarum [
43
,
101
]. S. bayanus was previously thought to be the parent of the
lager strain, S. pastorianus [
43
,
60
,
85
], but the hybridization event that produced lager brewing yeast is
now proven to have occurred between S. cerevisiae and S. eubayanus [
21
,
50
,
102
,
103
]. While S. bayanus
might not be the true hybrid parent of the most used brewing yeast in the world, it still forms natural
hybrids with other members of the Sss and was identified in these complexes in the fermentation of
wine [
62
,
85
,
104
]. While it was first isolated from turbid beer in 1927 [
105
], S. bayanus was also isolated
from beer, wine, fruit, and even soda [
47
]. S. bayanus is ellipsoid to elongate in shape, with a diameter
of 1–5
µ
m, and reproduces by multipolar budding. Research showed it to be a positive fermenter for
glucose, sucrose, and maltose. Other studies reported S. bayanus to show both positive and negative
fermentation of melibiose, but it does not ferment lactose or starch (Table 2).
S. bayanus is well-known as a fermenter of beer and cider [
43
,
105
,
106
], but is most commonly used
in wine [
96
,
103
,
107
]. It can be purchased from several commercial suppliers, but unfortunately several
commercially available strains were genetically identified as S. cerevisiae, including the famous Lalvin
EC-1118 strain that was originally typed S. bayanus [
108
,
109
]. S. bayanus ferments best in the upper end
of the lager strain temperature range of 10 to 21
◦
C [
77
,
101
], is moderately flocculant [
31
], and has a
fairly standard attenuation [
110
], as expected, given its genetic similarity to S. pastorianus lager yeast.
The commercially available hybrid of S. bayanus and S. cerevisiae available from Lallemand, Lalvin S6U,
is known to increase the varietal characteristics in white wine, and might produce elevated levels of
POF [
111
,
112
]. More research needs to be carried out with regards to the flavor profile of beers made
with S. bayanus, but the research on wine and its history as a potential lager strain means, it is capable
of fermenting remarkable lager style beers.
8. Other Saccharomyces spp. Used in Alcoholic Fermentation
Several other novel species of Saccharomyces used in alcoholic fermentation were determined to
be genetically distinct by current research but might not yet be included in the Saccharomyces sensu
stricto complex. S. abulensis is a novel species dubbed the “Santa Maria strain” and was isolated from
yeast originating from breweries in Madrid and Sevilla, Spain [
92
]. S. florentinus, formerly known as
S. pyriformis, is a species of yeast isolated from the scoby of traditionally fermented ginger beer, known as
“bees wine,” but is yet to be used in commercial productionof beer [
113
,
114
]. Three other strains included
in the phylogenetic tree of the Sss (Figure 3) exist—S. arboricola, S. jurei, and S. cariocanus—but research is
limited on their fermentation capacity. S. arboricola is a wild-type hybrid of S. bayanus and S. kudriavzevii,
which was isolated from oak and beechwood bark in China [
115
,
116
], and is currently being used in
sake production [
117
]. S. jurei is closely related to S. mikatae and S. paradoxus and was isolated from
a high altitude tree bark in France; little is known of its fermentative capacity [
118
]. S. cariocanus,
isolated from insects in South America [
119
], is a wild-type hybrid of S. paradoxus, which is capable of
fermenting sucrose and shows ethanol tolerance [120].
Fermentation 2020, 6, 116 9 of 16
These yeasts are not members of the Sss, but is likely to be included, as the complex underwent
many changes over the years, in accordance with the system employed in classifying yeast cultures.
Very little information exists on these yeasts’ ability to ferment beer or their use in a commercial
setting, but by contacting genetic banks and yeast culture collections directly, the strain type could be
obtained for further experimentation. There also exists multiple variants of S. cerevisiae, such as var.
boulardii, which is known to produce higher levels of polyphenols, and can thus be used in functional
probiotic beer [
121
–
126
]. Another variant, var. diastaticus, can cause over-attenuation [
127
–
129
],
which was discussed earlier as having the STA1 gene.
9. Conclusions
The non-cerevisiae Saccharomyces species discussed in this review, have the ability to ferment
glucose and maltose into ethanol, anaerobically. Most are members of the Saccharomyces sensu stricto
complex, while some are yet to be defined within the species complex classification. S. kudriavzevii is
available commercially as a hybrid with S. cerevisiae and can increase thiol aromatic qualities during
fermentation, at lower temperatures, making it ideal for distinctive lagers. S. paradoxus is also available
commercially as a hybrid with S. cerevisiae and showed increased fruity and floral esters in wine,
and also lends unique characteristics to African umqombothi beer. Hybrids of S. mikatae and S. cerevisiae
are not yet commercially available, but they were known to produce increased fruity and perfume
aromas even when fermented at low temperatures, marking its potential for remarkable lager beer
production. Due to debate on the classification and isolation process of S. uvarum in genetic research,
there is no commercially available version of this species, but it shows potential as a cryotolerant lager
yeast, with more character than S. pastorianus. After recent research, many commercially available
S. bayanus strains were reclassified as variants of S. cerevisiae, but the true hybrids of S. bayanus
and S. cerevisiae showed increased ethyl esters and spicy notes that could add a complexity to beer
production. While much of the research regarding flavor and aroma that is presented in this review
might be focused on wine, these species all have potential for novel fermentations and new sensory
experiences, if used in beer.
Author Contributions:
J.B. conceived the review topic, performed the research, and wrote the manuscript. G.F.
supervised the work, offered insight, and assisted with final editing of the manuscript. All authors have read and
agreed to the published version of the manuscript.
Funding:
This research was funded by the H.A. Jastro Shields Fellowship, Margrit Mondavi Graduate Fellowship,
George F. Stewart Memorial Fund, and Michael J. Lewis Endowment.
Acknowledgments:
Many thanks to Luxin Wang, Amanda Sinrod, and Jessie Liang of UC Davis Food Science
for edits on the first draft of this paper. Thanks to the UC Davis Food Science and Technology Department for
promoting research of beer.
Conflicts of Interest: The authors declare no conflict of interest.
References
1.
Legras, J.-L.; Merdinoglu, D.; Cornuet, J.-M.; Karst, F. Bread, beer and wine: Saccharomyces cerevisiae
diversity reflects human history. Mol. Ecol. 2007, 16, 2091–2102. [CrossRef]
2.
Meussdoerffer, F.G. A comprehensive history of beer brewing. In Handbook of Brewing; Elinger, H.M., Ed.;
Wiley-VCH Verlag GmbH & Co. KGaA: Weinheim, Germany, 2009; pp. 1–42. ISBN 9783527316748.
3.
Perruchini, E.; Glatz, C.; Hald, M.M.; Casana, J.; Toney, J.L. Revealing invisible brews: A new approach to
the chemical identification of ancient beer. J. Archaeol. Sci. 2018, 100, 176–190. [CrossRef]
4.
Liu, L.; Wang, J.; Rosenberg, D.; Zhao, H.; Lengyel, G.; Nadel, D. Fermented beverage and food storage in
13,000 y-old stone mortars at Raqefet Cave, Israel: Investigating Natufian ritual feasting. J. Archaeol. Sci. Rep.
2018, 21, 783–793. [CrossRef]
5.
Bamforth, C.W. The Horace Brown Medal. Forever in focus: Researches in malting and brewing sciences.
J. Inst. Brew. 2020. [CrossRef]
Fermentation 2020, 6, 116 10 of 16
6. Balling, K. Die Sacharometrische Bierprobe; Borrosch & André: Prague, Czechoslavakia, 1842.
7.
Joule, J.P. On the calorific effects of magneto-electricity, and on the mechanical value of heat. Lond. Edinb.
Dublin Philos. Mag. J. Sci. 1843, 23, 435–443. [CrossRef]
8.
Pasteur, L.
É
tudes sur le vin: Ses Maladies, Causes qui les Provoquent, Proc
é
d
é
s Nouveaux Pour le Conserver et Pour
le Vieillir, 2nd ed.; Imprimerie Impériale: Paris, France, 1866.
9.
Bamforth, C.W. Scientific Principles of Malting and Brewing; American Society of Brewing Chemists, Ed.;
American Society of Brewing Chemists: St. Paul, MN, USA, 2006; pp. 1–246. ISBN 1-881696-08-1.
10.
Ziliak, S.T. Retrospectives: Guinnessometrics: The economic foundation of “student’s”t. J. Econ. Perspect.
2008, 22, 199–216. [CrossRef]
11.
Sörensen, S.P.L. Enzymstudien. II. Mitteilung. Über die Messung und die Bedeutung der
Wasserstoffionenkoncentration bei enzymatischen Prozessen. Biochem. Z. 1909, 21, 131–304.
12.
Bamforth, C. Beer: Tap Into The Art and Science of Brewing, 3rd ed.; Oxford University Press: Oxford, UK, 2009;
p. 239. ISBN 978-0-19-530542-5.
13.
Wunderlich, S.; Zürcher, A.; Back, W. Enrichment of xanthohumol in the brewing process. Mol. Nutr. Food Res.
2005, 49, 874–881. [CrossRef] [PubMed]
14.
Magalh
ã
es, P.J.; Carvalho, D.O.; Cruz, J.M.; Guido, L.F.; Barros, A.A. Fundamentals and health benefits
of xanthohumol, a natural product derived from hops and beer. Nat. Prod. Commun.
2009
, 4, 591–610.
[CrossRef] [PubMed]
15.
He, Y.; Dong, J.; Yin, H.; Zhao, Y.; Chen, R.; Wan, X.; Chen, P.; Hou, X.; Liu, J.; Chen, L. Wort composition and
its impact on the flavour-active higher alcohol and ester formation of beer—A review. J. Inst. Brew.
2014
.
[CrossRef]
16.
Waterhouse, A.L.; Sacks, G.L.; Jeffery, D.W. Outline of wine production. In Understanding Wine Chemistry;
John Wiley & Sons, Ltd.: Chichester, UK, 2016; pp. 159–171. ISBN 9781118627808.
17. Fleet, G.H. Growth of yeasts during wine fermentations. J. Wine Res. 1990, 1, 211–223. [CrossRef]
18.
Tronchoni, J.; Gamero, A.; Arroyo-L
ó
pez, F.N.; Barrio, E.; Querol, A. Differences in the glucose and
fructose consumption profiles in diverse Saccharomyces wine species and their hybrids during grape juice
fermentation. Int. J. Food Microbiol. 2009, 134, 237–243. [CrossRef] [PubMed]
19. Moritz, E.R.; Morris, G.H. A Text-Book of the Science of Brewing; Spon: London, UK, 1891.
20.
Gallone, B.; Steensels, J.; Prahl, T.; Soriaga, L.; Saels, V.; Herrera-Malaver, B.; Merlevede, A.; Roncoroni, M.;
Voordeckers, K.; Miraglia, L.; et al. Domestication and Divergence of Saccharomyces cerevisiae Beer Yeasts.
Cell 2016, 166, 1397–1410.e16. [CrossRef] [PubMed]
21.
Fay, J.C.; Liu, P.; Ong, G.T.; Dunham, M.J.; Cromie, G.A.; Jeffery, E.W.; Ludlow, C.L.; Dudley, A.M. A polyploid
admixed origin of beer yeasts derived from European and Asian wine populations. PLoS Biol.
2019
, 17,
e3000147. [CrossRef] [PubMed]
22.
Olesen, K.; Felding, T.; Gjermansen, C.; Hansen, J. The dynamics of the brewing yeast transcriptome during
a production-scale lager beer fermentation. Fems Yeast Res. 2002, 2, 563–573. [CrossRef]
23.
Denby, C.M.; Li, R.A.; Vu, V.T.; Costello, Z.; Lin, W.; Chan, L.J.G.; Williams, J.; Donaldson, B.; Bamforth, C.W.;
Petzold, C.J.; et al. Industrial brewing yeast engineered for the production of primary flavor determinants in
hopped beer. Nat. Commun. 2018, 9, 965. [CrossRef]
24.
Olaniran, A.O.; Hiralal, L.; Mokoena, M.P.; Pillay, B. Flavour-active volatile compounds in beer:
Production, regulation and control. J. Inst. Brew. 2017, 123, 13–23. [CrossRef]
25.
Swiegers, J.H.; Bartowsky, E.J.; Henschke, P.A.; Pretorius, I.S. Yeast and bacterial modulation of wine aroma
and flavour. Aust. J. Grape Wine Res. 2005, 11, 139–173. [CrossRef]
26.
Swiegers, J.H.; Saerens, S.M.G.; Pretorius, I.S. The development of yeast strains as tools for adjusting the flavor
of fermented beverages to market specifications. In Biotechnology in Flavor Production; Havkin-Frenkel, D.,
Belanger, F.C., Eds.; Blackwell Publishing Ltd.: Oxford, UK, 2008; pp. 1–55. ISBN 9781405156493.
27.
Berg, J.M.; Tymoczko, J.L.; Stryer, L. Glycolysis is an Energy-Conversion Pathway in Many Organisms. 2002.
Available online: https://www.ncbi.nlm.nih.gov/books/NBK22593/ (accessed on 4 May 2020).
28.
Aranda, A.; Orozco, H.; Picazo, C.; Matallana, E. Yeast life span and its impact on food fermentations.
Fermentation 2019, 5, 37. [CrossRef]
29.
Dunham, M.J.; Badrane, H.; Ferea, T.; Adams, J.; Brown, P.O.; Rosenzweig, F.; Botstein, D. Characteristic
genome rearrangements in experimental evolution of Saccharomyces cerevisiae. Proc. Natl. Acad. Sci. USA
2002, 99, 16144–16149. [CrossRef]
Fermentation 2020, 6, 116 11 of 16
30.
Gresham, D.; Desai, M.M.; Tucker, C.M.; Jenq, H.T.; Pai, D.A.; Ward, A.; DeSevo, C.G.; Botstein, D.;
Dunham, M.J. The repertoire and dynamics of evolutionary adaptations to controlled nutrient-limited
environments in yeast. PLoS Genet. 2008, 4, e1000303. [CrossRef] [PubMed]
31.
Scannell, D.R.; Zill, O.A.; Rokas, A.; Payen, C.; Dunham, M.J.; Eisen, M.B.; Rine, J.; Johnston, M.; Hittinger, C.T.
The Awesome Power of Yeast Evolutionary Genetics: New Genome Sequences and Strain Resources for the
Saccharomyces sensu stricto Genus. G3 (Bethesda) 2011, 1, 11–25. [CrossRef] [PubMed]
32.
Large, C.R.L.; Hanson, N.A.; Tsouris, A.; Abou Saada, O.; Koonthongkaew, J.; Toyokawa, Y.; Schmidlin, T.;
Moreno-Habel, D.A.; McConnellogue, H.; Preiss, R.; et al. Genomic stability and adaptation of beer brewing
yeasts during serial repitching in the brewery. BioRxiv 2020. [CrossRef]
33.
Mensour, N.A.; Margaritis, A.; Briens, C.L.; Pilkington, H.; Russell, I. Application of immobilized yeast cells
in the brewing industry. In Immobilized Cells—Basics and Applications; Progress in Biotechnology; Elsevier:
Amsterdam, The Netherlands, 1996; Volume 11, pp. 661–671. ISBN 9780444819840.
34.
Marongiu, A.; Zara, G.; Legras, J.-L.; Del Caro, A.; Mascia, I.; Fadda, C.; Budroni, M. Novel starters for
old processes: Use of Saccharomyces cerevisiae strains isolated from artisanal sourdough for craft beer
production at a brewery scale. J. Ind. Microbiol. Biotechnol. 2015, 42, 85–92. [CrossRef] [PubMed]
35.
Canonico, L.; Comitini, F.; Ciani, M. Metschnikowia pulcherrima Selected Strain for Ethanol Reduction in Wine:
Influence of Cell Immobilization and Aeration Condition. Foods 2019, 8, 378. [CrossRef]
36.
Canonico, L.; Agarbati, A.; Comitini, F.; Ciani, M. Torulaspora delbrueckii in the brewing process: A new
approach to enhance bioflavour and to reduce ethanol content. Food Microbiol. 2016, 56, 45–51. [CrossRef]
37.
Varela, C. The impact of non-Saccharomyces yeasts in the production of alcoholic beverages.
Appl. Microbiol. Biotechnol. 2016, 100, 9861–9874. [CrossRef]
38.
Michel, M.; Meier-Dörnberg, T.; Jacob, F.; Methner, F.-J.; Wagner, R.S.; Hutzler, M. Review: Pure non-
Saccharomyces starter cultures for beer fermentation with a focus on secondary metabolites and practical
applications. J. Inst. Brew. 2016, 122, 569–587. [CrossRef]
39.
Basso, R.F.; Alcarde, A.R.; Portugal, C.B. Could non-Saccharomyces yeasts contribute on innovative brewing
fermentations? Food Res. Int. 2016, 86, 112–120. [CrossRef]
40.
Alonso-Del-Real, J.; Lair
ó
n-Peris, M.; Barrio, E.; Querol, A. Effect of Temperature on the Prevalence of
Saccharomyces Non cerevisiae Species against a S. cerevisiae Wine Strain in Wine Fermentation: Competition,
Physiological Fitness, and Influence in Final Wine Composition. Front. Microbiol. 2017, 8, 150. [CrossRef]
41.
P
é
rez-Torrado, R.; Barrio, E.; Querol, A. Alternative yeasts for winemaking: Saccharomyces non-cerevisiae
and its hybrids. Crit. Rev. Food Sci. Nutr. 2018, 58, 1780–1790. [CrossRef] [PubMed]
42.
Kodama, Y.; Kielland-Brandt, M.C.; Hansen, J. Lager brewing yeast. In Comparative Genomics; Sunnerhagen, P.,
Piskur, J., Eds.; Springer: Berlin/Heidelberg, Germany, 2006; pp. 145–164. ISBN 978-3-540-31480-6.
43.
Rainieri, S.; Kodama, Y.; Kaneko, Y.; Mikata, K.; Nakao, Y.; Ashikari, T. Pure and mixed genetic lines of
Saccharomyces bayanus and Saccharomyces pastorianus and their contribution to the lager brewing strain
genome. Appl. Environ. Microbiol. 2006, 72, 3968–3974. [CrossRef]
44.
Gibson, B.; Liti, G. Saccharomyces pastorianus: Genomic insights inspiring innovation for industry. Yeast
2015
,
32, 17–27. [CrossRef] [PubMed]
45.
White, C.; Zainasheff, J. Yeast: The Practical Guide To Beer Fermentation; Brewers Publications: Boulder, CO,
USA, 2010; p. 300. ISBN 978-0937381960.
46.
Mortimer, R.K. Evolution and variation of the yeast (Saccharomyces) genome. Genome Res.
2000
, 10, 403–409.
[CrossRef] [PubMed]
47.
Naumov, G.I.; James, S.A.; Naumova, E.S.; Louis, E.J.; Roberts, I.N. Three new species in the Saccharomyces
sensu stricto complex: Saccharomyces cariocanus, Saccharomyces kudriavzevii and Saccharomyces mikatae. Int. J.
Syst. Evol. Microbiol. 2000, 50, 1931–1942. [CrossRef]
48.
Borneman, A.R.; Pretorius, I.S. Genomic insights into the Saccharomyces sensu stricto complex. Genetics
2015
,
199, 281–291. [CrossRef]
49.
Naumov, G. Genetic identification of biological species in the Saccharomyces sensu stricto complex. J. Ind.
Microbiol. Biotechnol. 1996, 17, 295–302. [CrossRef]
50.
Bing, J.; Han, P.-J.; Liu, W.-Q.; Wang, Q.-M.; Bai, F.-Y. Evidence for a Far East Asian origin of lager beer yeast.
Curr. Biol. 2014, 24, R380-1. [CrossRef]
Fermentation 2020, 6, 116 12 of 16
51. Fay, J.C. Tapping into yeast diversity. Mol. Ecol. 2012, 21, 5387–5389. [CrossRef]
52.
Sampaio, J.P.; Gonçalves, P. Natural populations of Saccharomyces kudriavzevii in Portugal are associated with
oak bark and are sympatric with S. cerevisiae and S. paradoxus. Appl. Environ. Microbiol.
2008
, 74, 2144–2152.
[CrossRef]
53.
Erny, C.; Raoult, P.; Alais, A.; Butterlin, G.; Delobel, P.; Matei-Radoi, F.; Casaregola, S.; Legras, J.L. Ecological
success of a group of Saccharomyces cerevisiae/Saccharomyces kudriavzevii hybrids in the northern european
wine-making environment. Appl. Environ. Microbiol. 2012, 78, 3256–3265. [CrossRef] [PubMed]
54.
Peris, D.; P
é
rez-Torrado, R.; Hittinger, C.T.; Barrio, E.; Querol, A. On the origins and industrial applications
of Saccharomyces cerevisiae × Saccharomyces kudriavzevii hybrids. Yeast 2018, 35, 51–69. [CrossRef]
55.
Kellis, M.; Patterson, N.; Endrizzi, M.; Birren, B.; Lander, E.S. Sequencing and comparison of yeast species to
identify genes and regulatory elements. Nature 2003, 423, 241–254. [CrossRef] [PubMed]
56.
Gonz
á
lez, S.S.; Barrio, E.; Querol, A. Molecular characterization of new natural hybrids of Saccharomyces
cerevisiae and S. kudriavzevii in brewing. Appl. Environ. Microbiol.
2008
, 74, 2314–2320. [CrossRef] [PubMed]
57.
Scholtes, C.; Nizet, S.; Collin, S. Guaiacol and 4-methylphenol as specific markers of torrefied malts. Fate
of volatile phenols in special beers through aging. J. Agric. Food Chem.
2014
, 62, 9522–9528. [CrossRef]
[PubMed]
58.
Henriques, D.; Alonso-Del-Real, J.; Querol, A.; Balsa-Canto, E. Saccharomyces cerevisiae and S. kudriavzevii
Synthetic Wine Fermentation Performance Dissected by Predictive Modeling. Front. Microbiol.
2018
, 9, 88.
[CrossRef] [PubMed]
59.
Gallone, B.; Steensels, J.; Mertens, S.; Dzialo, M.C.; Gordon, J.L.; Wauters, R.; Theßeling, F.A.; Bellinazzo, F.;
Saels, V.; Herrera-Malaver, B.; et al. Interspecific hybridization facilitates niche adaptation in beer yeast.
Nat. Ecol. Evol. 2019, 3, 1562–1575. [CrossRef]
60.
Groth, C.; Hansen, J.; Piskur, J. A natural chimeric yeast containing genetic material from three species. Int. J.
Syst. Bacteriol. 1999, 49, 1933–1938. [CrossRef]
61.
Masneuf, I.; Hansen, J.; Groth, C.; Piskur, J.; Dubourdieu, D. New hybrids between Saccharomyces sensu stricto
yeast species found among wine and cider production strains. Appl. Environ. Microbiol.
1998
, 64, 3887–3892.
[CrossRef]
62.
Belloch, C.; Orlic, S.; Barrio, E.; Querol, A. Fermentative stress adaptation of hybrids within the Saccharomyces
sensu stricto complex. Int. J. Food Microbiol. 2008, 122, 188–195. [CrossRef]
63.
Salvad
ó
, Z.; Arroyo-L
ó
pez, F.N.; Guillam
ó
n, J.M.; Salazar, G.; Querol, A.; Barrio, E. Temperature adaptation
markedly determines evolution within the genus Saccharomyces. Appl. Environ. Microbiol.
2011
, 77,
2292–2302. [CrossRef]
64.
VIN 7. Available online: http://www.oenobrands.com/en/our-brands/anchor/new-world-wine-yeasts/
product-data-sheets/vin-7 (accessed on 27 April 2020).
65.
Jolly, N.P.; Augustyn, O.P.H.; Pretorius, I.S. The Role and Use of Non-Saccharomyces Yeasts in Wine
Production. SAJEV 2017, 27. [CrossRef]
66.
Martini, A.V.; Martini, A. A.V.; Martini, A. A proposal for correct nomenclature of the domesticated species
of the genus saccharomyces. In Biotechnology Applications in Beverage Production; Cantarelli, C., Lanzarini, G.,
Eds.; Springer: Dordrecht, The Netherlands, 1989; pp. 1–16. ISBN 978-94-009-1113-0.
67.
Sniegowski, P.D.; Dombrowski, P.G.; Fingerman, E. Saccharomyces cerevisiae and Saccharomyces paradoxus
coexist in a natural woodland site in North America and display different levels of reproductive isolation
from European conspecifics. Fems Yeast Res. 2002, 1, 299–306. [CrossRef] [PubMed]
68.
Hyma, K.E.; Fay, J.C. Mixing of vineyard and oak-tree ecotypes of Saccharomyces cerevisiae in North American
vineyards. Mol. Ecol. 2013, 22, 2917–2930. [CrossRef]
69.
Charron, G.; Leducq, J.-B.; Bertin, C.; Dub
é
, A.K.; Landry, C.R. Exploring the northern limit of the distribution
of Saccharomyces cerevisiae and Saccharomyces paradoxus in North America. Fems Yeast Res. 2014, 14, 281–288.
[CrossRef] [PubMed]
70.
Liti, G.; Carter, D.M.; Moses, A.M.; Warringer, J.; Parts, L.; James, S.A.; Davey, R.P.; Roberts, I.N.; Burt, A.;
Koufopanou, V.; et al. Population genomics of domestic and wild yeasts. Nature
2009
, 458, 337–341.
[CrossRef] [PubMed]
Fermentation 2020, 6, 116 13 of 16
71.
Roop, J.I.; Brem, R.B. Rare variants in hypermutable genes underlie common morphology and growth traits
in wild Saccharomyces paradoxus. Genetics 2013, 195, 513–525. [CrossRef]
72.
Redzepovi´c, S.; Orli´c, S.; Sikora, S.; Majdak, A.; Pretorius, I.S. Identification and characterization
of Saccharomyces cerevisiae and Saccharomyces paradoxus strains isolated from Croatian vineyards.
Lett. Appl. Microbiol. 2002, 35, 305–310. [CrossRef]
73.
Orlic, S.; Redzepovic, S.; Jeromel, A.; Herjavec, S.; Iacumin, L. Influence of indigenous Saccharomyces
paradoxus strains on Chardonnay wine fermentation aroma. Int. J. Food Sci. Technol.
2007
, 42, 95–101.
[CrossRef]
74.
Majdak, A.; Herjavec, S.; Orlic, S.; Redzepovic, S.; Mirosevic, N. Comparison of Wine Aroma Compounds
Produced by Saccharomyces paradoxus and Saccharomyces cerevisiae Strains. Food Technol. Biotechnol.
2002
, 40,
103–109.
75.
Naumova, E.; Korshunova, I.; Jespersen, L.; Naumov, G. Molecular genetic identification of sensu stricto
strains from African sorghum beer. Fems Yeast Res. 2003, 3, 177–184. [CrossRef]
76.
Sweeney, J.; Kuehne, H.; Sniegowski, P. Sympatric natural and populations have different thermal growth
profiles. Fems Yeast Res. 2004, 4, 521–525. [CrossRef]
77.
Gonçalves, P.; Val
é
rio, E.; Correia, C.; de Almeida, J.M.G.C.F.; Sampaio, J.P. Evidence for divergent evolution
of growth temperature preference in sympatric Saccharomyces species. PLoS ONE
2011
, 6, e20739. [CrossRef]
78.
Rollero, S.; Bloem, A.; Ortiz-Julien, A.; Camarasa, C.; Divol, B. Fermentation performances and aroma
production of non-conventional wine yeasts are influenced by nitrogen preferences. Fems Yeast Res.
2018
, 18.
[CrossRef] [PubMed]
79.
Dunn, B.; Richter, C.; Kvitek, D.J.; Pugh, T.; Sherlock, G. Analysis of the Saccharomyces cerevisiae pan-genome
reveals a pool of copy number variants distributed in diverse yeast strains from differing industrial
environments. Genome Res. 2012, 22, 908–924. [CrossRef]
80.
Bellon, J.R.; Schmid, F.; Capone, D.L.; Dunn, B.L.; Chambers, P.J. Introducing a new breed of wine yeast:
Interspecific hybridisation between a commercial Saccharomyces cerevisiae wine yeast and Saccharomyces
mikatae. PLoS ONE 2013, 8, e62053. [CrossRef] [PubMed]
81.
Bellon, J.; Schmidt, S.; Solomon, M. Case study: Development of Saccharomyces cerevisiae
×
Saccharomyces mikatae
wine yeast hybrids and their potential to deliver alternative wine styles. AWRI Tech. Rev. 2019, 241, 6–11.
82.
Pulvirenti, A.; Nguyen, H.; Caggia, C.; Giudici, P.; Rainieri, S.; Zambonelli, C. Saccharomyces uvarum, a proper
species within Saccharomyces sensu stricto. FEMS Microbiol. Lett. 2000, 192, 191–196. [CrossRef]
83. Nguyen, H.-V.; Gaillardin, C. Evolutionary relationships between the former species Saccharomyces uvarum
and the hybrids Saccharomyces bayanus and Saccharomyces pastorianus; reinstatement of Saccharomyces uvarum
(Beijerinck) as a distinct species. FEMS Yeast Res. 2005, 5, 471–483. [CrossRef]
84.
Rainieri, S.; Zambonelli, C.; Hallsworth, J.E.; Pulvirenti, A.; Giudici, P. Saccharomyces uvarum, a distinct group
within Saccharomyces sensu stricto. FEMS Microbiol. Lett. 1999, 177, 177–185. [CrossRef]
85.
Naumova, E.S.; Naumov, G.I.; Masneuf-Pomar
è
de, I.; Aigle, M.; Dubourdieu, D. Molecular genetic study of
introgression between Saccharomyces bayanus and S. cerevisiae. Yeast
2005
, 22, 1099–1115. [CrossRef] [PubMed]
86.
Demuyter, C.; Lollier, M.; Legras, J.L.; Le Jeune, C. Predominance of Saccharomyces uvarum during spontaneous
alcoholic fermentation, for three consecutive years, in an Alsatian winery. J. Appl. Microbiol.
2004
, 97,
1140–1148. [CrossRef] [PubMed]
87.
Tosi, E.; Azzolini, M.; Guzzo, F.; Zapparoli, G. Evidence of different fermentation behaviours of two indigenous
strains of Saccharomyces cerevisiae and Saccharomyces uvarum isolated from Amarone wine. J. Appl. Microbiol.
2009, 107, 210–218. [CrossRef] [PubMed]
88.
Rodr
í
guez, M.E.; P
é
rez-Trav
é
s, L.; Sangorr
í
n, M.P.; Barrio, E.; Querol, A.; Lopes, C.A. Saccharomyces uvarum
is responsible for the traditional fermentation of apple chicha in Patagonia. FEMS Yeast Res.
2017
, 17.
[CrossRef] [PubMed]
89.
Rodr
í
guez, M.E.; P
é
rez-Trav
é
s, L.; Sangorr
í
n, M.P.; Barrio, E.; Lopes, C.A. Saccharomyces eubayanus
and Saccharomyces uvarum associated with the fermentation of Araucaria araucana seeds in Patagonia.
FEMS Yeast Res. 2014, 14, 948–965. [CrossRef] [PubMed]
Fermentation 2020, 6, 116 14 of 16
90.
Beijerinck, M.W. Über Regeneration der Sporenbildung bei Alkoholhefen, wo diese Function im Verschwinden
begriffen ist. Cent. Bakteriol. Parasitenkd. 1898, 4, 721–730.
91.
Krogerus, K.; Preiss, R.; Gibson, B. A Unique Saccharomyces cerevisiae
×
Saccharomyces uvarum Hybrid Isolated
from Norwegian Farmhouse Beer: Characterization and Reconstruction. Front. Microbiol.
2018
, 9, 2253.
[CrossRef]
92.
Nguyen, H.-V.; Boekhout, T. Characterization of Saccharomyces uvarum (Beijerinck, 1898) and related hybrids:
Assessment of molecular markers that predict the parent and hybrid genomes and a proposal to name yeast
hybrids. Fems Yeast Res. 2017, 17. [CrossRef]
93.
Krogerus, K.; Gibson, B. A re-evaluation of diastatic Saccharomyces cerevisiae strains and their role in brewing.
Appl. Microbiol. Biotechnol. 2020, 104, 3745–3756. [CrossRef]
94.
Smukowski Heil, C.S.; Large, C.R.L.; Patterson, K.; Hickey, A.S.-M.; Yeh, C.-L.C.; Dunham, M.J. Temperature
preference can bias parental genome retention during hybrid evolution. PLoS Genet.
2019
, 15, e1008383.
[CrossRef]
95.
Morgan, S.C.; Haggerty, J.J.; Jiranek, V.; Durall, D.M. Competition between Saccharomyces cerevisiae and
Saccharomyces uvarum in Controlled Chardonnay Wine Fermentations. Am. J. Enol. Vitic. 2020. [CrossRef]
96.
Feuillat, M. Use of Yeasts in Burgandy and In Other Regions: Fermentation and Ading on Lees. In Yeast’s
Contribution to the Sensory Profile of Wine: Maintaining Typicity and Biodiversity in the Context of Globalization;
Lallemand, S.A.S., Ed.; Entretiens Scientifiques: Wiesbaden, Germany, 2005; Volume XVII, pp. 27–32.
97.
Le Jeune, C.; Lollier, M.; Demuyter, C.; Erny, C.; Legras, J.-L.; Aigle, M.; Masneuf-Pomar
è
de, I. Characterization
of natural hybrids of Saccharomyces cerevisiae and Saccharomyces bayanus var. uvarum. FEMS Yeast Res.
2007
,
7, 540–549. [CrossRef] [PubMed]
98.
Available Microbial Strains—The Australian Wine Research Institute. Available online: https://www.awri.com.
au/research_and_development/wine-microorganism/winemaking-yeast-and-bacterial-strains/ (accessed on
3 May 2020).
99.
Caudy, A.A.; Guan, Y.; Jia, Y.; Hansen, C.; DeSevo, C.; Hayes, A.P.; Agee, J.; Alvarez-Dominguez, J.R.;
Arellano, H.; Barrett, D.; et al. A new system for comparative functional genomics of Saccharomyces yeasts.
Genetics 2013, 195, 275–287. [CrossRef]
100.
Vaughan Martini, A.; Kurtzman, C.P. Deoxyribonucleic Acid Relatedness among Species of the Genus
Saccharomyces Sensu Stricto. Int. J. Syst. Bacteriol. 1985, 35, 508–511. [CrossRef]
101.
Nguyen, H.-V.; Legras, J.-L.; Neuv
é
glise, C.; Gaillardin, C. Deciphering the hybridisation history leading to
the Lager lineage based on the mosaic genomes of Saccharomyces bayanus strains NBRC1948 and CBS380.
PLoS ONE 2011, 6, e25821. [CrossRef] [PubMed]
102.
Libkind, D.; Hittinger, C.T.; Val
é
rio, E.; Gonçalves, C.; Dover, J.; Johnston, M.; Gonçalves, P.; Sampaio, J.P.
Microbe domestication and the identification of the wild genetic stock of lager-brewing yeast. Proc. Natl.
Acad. Sci. USA 2011, 108, 14539–14544. [CrossRef] [PubMed]
103.
De Almeida, P.M.C. Microbe Domestication and the Identification of the Wild Genetic Stock of Wine
Yeasts. Proc. Natl. Acad. Sci. USA
2016
. Available online: http://hdl.handle.net/10362/19871 (accessed on
24 November 2020).
104.
Gonz
á
lez, S.S.; Barrio, E.; Gafner, J.; Querol, A. Natural hybrids from Saccharomyces cerevisiae, Saccharomyces
bayanus and Saccharomyces kudriavzevii in wine fermentations. FEMS Yeast Res.
2006
, 6, 1221–1234. [CrossRef]
105. Wendland, J. Lager yeast comes of age. Eukaryot. Cell 2014, 13, 1256–1265. [CrossRef]
106.
Sicard, D.; Legras, J.-L. Bread, beer and wine: Yeast domestication in the Saccharomyces sensu stricto complex.
C. R. Biol. 2011, 334, 229–236. [CrossRef]
107.
Ugliano, M.; Fedrizzi, B.; Siebert, T.; Travis, B.; Magno, F.; Versini, G.; Henschke, P.A. Effect of nitrogen
supplementation and Saccharomyces species on hydrogen sulfide and other volatile sulfur compounds in
shiraz fermentation and wine. J. Agric. Food Chem. 2009, 57, 4948–4955. [CrossRef] [PubMed]
108.
Fern
á
ndez-Espinar, M. Study of the authenticity of commercial wine yeast strains by molecular techniques.
Int. J. Food Microbiol. 2001, 70, 1–10. [CrossRef]
Fermentation 2020, 6, 116 15 of 16
109.
Hoff, J.W. Molecular Typing of Wine Yeasts: Evaluation of Typing Techniques and Establishment of a
Database. 2012. Available online: https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.933.7961&
rep=rep1&type=pdf (accessed on 1 May 2020).
110.
Nakao, Y.; Kanamori, T.; Itoh, T.; Kodama, Y.; Rainieri, S.; Nakamura, N.; Shimonaga, T.; Hattori, M.;
Ashikari, T. Genome sequence of the lager brewing yeast, an interspecies hybrid. DNA Res.
2009
, 16, 115–129.
[CrossRef] [PubMed]
111.
Cordente, A.G.; Curtin, C.D.; Varela, C.; Pretorius, I.S. Flavour-active wine yeasts. Appl. Microbiol. Biotechnol.
2012, 96, 601–618. [CrossRef]
112.
Hisamoto, M.; Furuya, T.; Yanagida, A.; Okuda, T.; Sato, M. Phenolic off Flavor Characterization of
Commercially Available Wine Yeasts and Selection of the Yeast for Koshu Winemaking. J. ASEV Jpn.
2010
,
21, 112–117.
113.
Ward, H.M. V. the ginger-beer plant, and the organisms composing it: A contribution to the study of
fermentation-yeasts and bacteria. Philos. Trans. R. Soc. Lond. B 1892, 183, 125–197. [CrossRef]
114.
Pidoux, M. The microbial flora of sugary kefir grain (the gingerbeer plant): Biosynthesis of the grain
fromLactobacillus hilgardii producing a polysaccharide gel. World J. Microbiol. Biotechnol.
1989
, 5, 223–238.
[CrossRef]
115.
Naumov, G.I.; Naumova, E.S.; Masneuf-Pomar
è
de, I. Genetic identification of new biological species
Saccharomyces arboricolus Wang et Bai. Antonie Van Leeuwenhoek 2010, 98, 1–7. [CrossRef]
116.
Wang, S.-A.; Bai, F.-Y. Saccharomyces arboricolus sp. nov., a yeast species from tree bark. Int. J. Syst.
Evol. Microbiol. 2008, 58, 510–514. [CrossRef]
117.
Winans, M.J.; Yamamoto, Y.; Fujimaru, Y.; Kusaba, Y.; Gallagher, J.E.G.; Kitagaki, H. Saccharomyces arboricola
and Its Hybrids’ Propensity for Sake Production: Interspecific Hybrids Reveal Increased Fermentation
Abilities and a Mosaic Metabolic Profile. Fermentation 2020, 6, 14. [CrossRef]
118.
Naseeb, S.; James, S.A.; Alsammar, H.; Michaels, C.J.; Gini, B.; Nueno-Palop, C.; Bond, C.J.; McGhie, H.;
Roberts, I.N.; Delneri, D. Suppl. Saccharomyces jurei sp. nov., isolation and genetic identification of a novel
yeast species from Quercus robur. Int. J. Syst. Evol. Microbiol. 2017, 67, 2046–2052. [CrossRef] [PubMed]
119.
Liti, G.; Barton, D.B.H.; Louis, E.J. Sequence diversity, reproductive isolation and species concepts in
Saccharomyces. Genetics 2006, 174, 839–850. [CrossRef] [PubMed]
120.
Barbosa, R.; Almeida, P.; Safar, S.V.B.; Santos, R.O.; Morais, P.B.; Nielly-Thibault, L.; Leducq, J.-B.; Landry, C.R.;
Gonçalves, P.; Rosa, C.A.; et al. Evidence of Natural Hybridization in Brazilian Wild Lineages of Saccharomyces
cerevisiae. Genome Biol. Evol. 2016, 8, 317–329. [CrossRef] [PubMed]
121.
de Paula, B.P.; Ch
á
vez, D.W.H.; Lemos Junior, W.J.F.; Guerra, A.F.; Corr
ê
a, M.F.D.; Pereira, K.S.;
Coelho, M.A.Z. Growth Parameters and Survivability of Saccharomyces boulardii for Probiotic Alcoholic
Beverages Development. Front. Microbiol. 2019, 10, 2092. [CrossRef] [PubMed]
122.
Capece, A.; Romaniello, R.; Pietrafesa, A.; Siesto, G.; Pietrafesa, R.; Zambuto, M.; Romano, P. Use of
Saccharomyces cerevisiae var. boulardii in co-fermentations with S. cerevisiae for the production of craft beers
with potential healthy value-added. Int. J. Food Microbiol. 2018, 284, 22–30. [CrossRef]
123.
Mulero-Cerezo, J.; Briz-Red
ó
n,
Á
.; Serrano-Aroca,
Á
. Saccharomyces cerevisiae var. boulardii: Valuable probiotic
starter for craft beer production. Appl. Sci. 2019, 9, 3250. [CrossRef]
124.
Van der Aa Kühle, A.; Jespersen, L. The taxonomic position of Saccharomyces boulardii as evaluated by
sequence analysis of the D1/D2 domain of 26S rDNA, the ITS1-5.8S rDNA-ITS2 region and the mitochondrial
cytochrome-c oxidase II gene. Syst. Appl. Microbiol. 2003, 26, 564–571. [CrossRef]
125.
Ram
í
rez-Cota, G.Y.; L
ó
pez-Villegas, E.O.; Jim
é
nez-Aparicio, A.R.; Hern
á
ndez-S
á
nchez, H. Modeling the
Ethanol Tolerance of the Probiotic Yeast Saccharomyces cerevisiae var. boulardii CNCM I-745 for its Possible
Use in a Functional Beer. Probiotics Antimicrob. Proteins 2020. [CrossRef]
126.
Sampaolesi, S.; Gamba, R.R.; De Antoni, G.L.; Le
ó
n Pel
á
ez,
Á
.M. Potentiality of yeasts obtained as beer
fermentation residue to be used as probiotics. LWT 2019, 113, 108251. [CrossRef]
127.
Sakai, K.; Fukui, S.; Yabuuchi, S.; Aoyagi, S.; Tsumura, Y. Expression of the saccharomyces diastaticus sta1 gene
in brewing yeasts. ASBCJ 1989, 47, 87–91. [CrossRef]
Fermentation 2020, 6, 116 16 of 16
128.
Meier-Dörnberg, T.; Kory, O.I.; Jacob, F.; Michel, M.; Hutzler, M. Saccharomyces cerevisiae variety diastaticus
friend or foe?-spoilage potential and brewing ability of different Saccharomyces cerevisiae variety diastaticus
yeast isolates by genetic, phenotypic and physiological characterization. FEMS Yeast Res.
2018
, 18. [CrossRef]
[PubMed]
129.
Yamauchi, H.; Yamamoto, H.; Shibano, Y.; Amaya, N.; Saeki, T. Rapid methods for detecting Saccharomyces
diastaticus, a beer spoilage yeast, using the polymerase chain reaction. ASBCJ 1998, 56, 58–63. [CrossRef]
Publisher’s Note:
MDPI stays neutral with regard to jurisdictional claims in published maps and institutional
affiliations.
©
2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).