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Interestingly, the study also found that the dominate genera of microbes was different between the two years sampled. In 2010, there were more Firmicutes (which includes LAB) and more Actinobacteria, and less Bacteroidetes. In 2011, the reverse was found with fewer Firmicutes and Actinobacteria, and more Bacteroidetes <ref name="Lievens3">[https://www.youtube.com/watch?v=5mttD027PMU Bart Lievens - Bacterial community dynamics during industrial malting, at the Belgian Brewers Conference 2015.]</ref> (~15 mins in).
The study examined LAB populations specifically due to their potential to help with malt stability and quality <ref>[http://www.researchgate.net/profile/Arja_Laitila/publication/7062169_Lactobacillus_plantarum_and_Pediococcus_pentosaceus_starter_cultures_as_a_tool_for_microflora_management_in_malting_and_for_enhancement_of_malt_processability/links/00b7d529ed5568640a000000.pdf Lactobacillus plantarum and Pediococcus pentosaceus Starter Cultures as a Tool for Microflora Management in Malting and for Enhancement of Malt Processability. ARJA LAITILA, HANNELE SWEINS, ARVI VILPOLA, ERJA KOTAVIITA, JUHANI OLKKU, SILJA HOME, AND AULI HAIKARA. 2006.]</ref>. ''Streptococcus'' was the most abundant genus of bacteria in all samples. In 2010, ''Lactobacillus'' was more abundant than it was in 2011. ''Lactococcus'' and ''Weisella'' were more abundant in 2011 than in 2010. Maltster 1 had a greater abundance of both ''Lactococcus'' and ''Weisella'' in 2011 over Maltster 2. In 2010, ''Lactobacillus'' was more abundant for Maltster 2 than it was for Maltster 1. This showed that microbial populations differ not only between malt houses, but also between barley harvest years <ref name="Lievens3"></ref> (~17 mins in). Sometimes [[Alternative_Bacteria_Sources#Culturing_Lactobacillus_From_Grains|culturing from malted grains]] turns out bad perhaps not because of the brewer, but because of the dominate cultures on the malted grains.
Another study focused on microbial populations in an American coolship brewery detected only ''Pediococcus'' on grain samples, but the lack of detection of other microbes was attributed to the methods used <ref>[http://elifesciences.org/content/4/e04634 Mapping microbial ecosystems and spoilage-gene flow in breweries highlights patterns of contamination and resistance. Nicholas A Bokulich, Jordyn Bergsveinson, Barry Ziola, David A Mills. March, 2015.]</ref>.