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''Saccharomyces cerevisiae'' var. ''diastaticus'' is a variant of ''S. cerevisiae'' that can ferment certain types of starches and dextrins, and has been identified as a contaminant in breweries and is responsible for a few large recalls. This variant can produce extracellular glucoamylase that can break down starches into simpler sugars that are then fermented by the yeast and cause over-carbonation. It can grow at 37°C The capability to produce this enzyme is encoded by the STA1, STA2, or STA3 genes. Not all strains containing one of these genes produces the glucoamylase enzyme, and can it was found that STA10 is also remain viable at refrigeration temperatures required to produce the enzyme <ref>[https://link.springer.com/article/10.1007%2FBF00365634 STA10: A gene involved in the control of starch utilization by Saccharomyces. Julio Polaina, Melanie Y. Wiggs. 1983.]]</ref><ref>[http://wwwonlinelibrary.ebc2017wiley.com/inhaltdoi/uploads10.1002/P095_Begrowyea.pdf Wade Begrow. "Recent notable microbiological contaminations1102/full Structural analysis of craft beer in glucoamylase encoded by the United States"STA1 gene of Saccharomyces cerevisiae (var. diastaticus). Presentation poster at EBC 2017Ana Cristina Adam, Lorena Latorre-Garcia, Julio Polaina. Retrieved 11/19/20172004.]</ref>. WY3711 saison yeast, which originated from Basserie ThiriezHowever, it has been determined to be this subspecies reported by some microbiologists that most (if not all) brewing strains that contain STA1, STA2, or STA3 do produce the glucoamylase enzyme <ref name="preiss_diastaticusmbaa_diastaticus">[http://masterbrewerspodcast.com/068-diastaticus-part-1 Matthew Peetz of Inland Island and Tobias Fischborn of Lallemand. "Master Brewers Association Podcast" 12/25/2017.]</ref>(~16 mins). In the This report is directly contradicted by White Labs regarding their strains [https://whitelabs.com/yeast-bank/wlp590-french-saison-ale-yeast WLP590], [Saccharomyces#Commercial_Farmhousehttps://www.whitelabs.2FBelgian_Strains_of_Saccharomyces|commercial culturecom/yeast-bank/wlp099-super-high-gravity-ale-yeast WLP099], and [https://www.whitelabs.com/yeast-bank/wlp045-scotch-whisky-yeast WLP045] lists below where we believe a lab (it is selling this strain of yeast or might likely that the strains reported by other microbiologists to be selling diastaticus are the same as these White Labs strains, but this strain of has not been verified). This yeasthas also reportedly been detected using [http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1981.tb04005.x/pdf LCSM agar plates], we note that it is determined/suspected to be although other species of wild ''diastaticusSaccharomyces''yeast can grow on this media <ref name="mbaa_diastaticus" />(~18 mins) and PCR DNA analysis is required to give a positive identification of diastaticus. The Belle Saison strain Diastaticus contamination in breweries has been a recent hot topic, and the source of some contaminations has been suspected to come from Lallemand is killer neutralcertain yeast suppliers <ref>[https://www.courthousenews.com/wp-content/uploads/2017/11/Left-Hand-v-White-Labs-COMPLAINT.pdf District Court, Boulder County, which means that killer wine strains will not kill it (it is not verified if Belle Saison is the same as WY3711Colorado. Case Number 2017CV31132. Filed 11/14/2017.]</Thiriez)ref>.

''S. cerevisiae'' var ''diastaticus'' can grow at 37°C and can also remain viable at refrigeration temperatures <ref>[http://www.ebc2017.com/inhalt/uploads/P095_Begrow.pdf Wade Begrow. "Recent notable microbiological contaminations of craft beer in the United States". Presentation poster at EBC 2017. Retrieved 11/19/2017.]</ref>. WY3711 saison yeast, which originated from Basserie Thiriez, has been determined to be this subspecies <ref name="preiss_diastaticus" />. In the [[Saccharomyces#Commercial_Farmhouse.2FBelgian_Strains_of_Saccharomyces|commercial culture]] lists below where we believe a lab is selling this strain of yeast or might be selling this strain of yeast, we note that it is determined/suspected to be ''diastaticus''. The Belle Saison strain from Lallemand is killer neutral, which means that killer wine strains will not kill it (it is not verified if Belle Saison is the same as WY3711/Thiriez, although it is suspected to be). Some hints as to which White Labs products might be ''diastaticus'' have been deduced from the Gallone et al. study that published DNA sequencing on most of the yeast strains in the White Labs bank. However, the codes used in the Gallone paper for each strain of yeast were not defined as far as which White Labs products correspond to which code used in the study. Some of the codes have been speculated on which White Labs strains they might refer to (see [[Saccharomyces#History_of_Domestication|History of Domestication]] above). The strains from the Gallone paper that appear to contain STA1 are Beer002, Wine019, Beer092 and Beer059. The Beer059 code might correspond to WLP026 according to this speculative [https://www.facebook.com/groups/MilkTheFunk/permalink/1400297539998456/?comment_id=1908170505877821&comment_tracking=%7B%22tn%22%3A%22R0%22%7D table], which has had reports of high attenuation. It is not clear at this time whether this strain is ''diastaticus'' or not <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1400297539998456/?comment_id=1909596632401875&reply_comment_id=1910328215662050&comment_tracking=%7B%22tn%22%3A%22R9%22%7D MTF thread on STA1 gene and White Labs strains that might have it or not. Milk The Funk Facebook group. 12/07/2017.]</ref>.