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===Malted Barley===
Most historical studies on microbe populations on malt have been done using lab media such as agar plates, which are thought to not be as effective at analyzing the overall population as recent DNA sequencing approaches, such as "454 amplicon pyrosequencing". A recent study took this approach to measuring microbial diversity on barley and malt. This study looked at two malting houses during two different years (2010 and 2011). It found that on malt, the largest communities of bacteria were found to include ''Enterobacter'', ''Sphingobacterium'', ''Weissella'', ''Lactobacillus'', ''Lactococcus'', ''Streptococcus'', ''Acinetobacter'', and ''Strenotrophomonas'', ''Leuconostoc'', ''Pseudomonas'', ''Wautersiella'', ''Cryseobacterium'', ''Curtobacterium'', and ''Propionobacterium'' <ref name="Lievens2">[Bacterial community dynamics during industrial malting, with an emphasis on lactic acid bacteria. A. Justé, S. Malfliet, M. Waud, S. Crauwels, L. De Cooman, G. Aerts, T.L. Marsh, S. Ruyters, K. Willems, P. Busschaerta, B. Lievens. 2014.]</ref>. Interestingly, the study also found that the majority genera of microbes was different between the two years sampled. In Progress2010, there were more ''Firmicutes'' species (which includes LAB) and more 'Actinobacteria'', and less ''Bacteroidetes''. In 2011, there were fewer of both ''Firmicutes'' and ''Actinobacteria'', but 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 quality. ''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 great 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 harvest years, but also malt houses <ref name="Lievens3"></ref> (~17 mins in). * See [https://lirias.kuleuven.be/bitstream/123456789/323419/2/Juste_et_al._FEMS2011_mout%20definitief.pdf this study] for a list of microbes that were found on malt using DNA methods.* See [https://lirias.kuleuven.be/bitstream/123456789/323403/2/Just%C3%A9%20et%20al.%202011_Microflora%20during%20Malting%20of%20Barley%20Overview%20and%20Impact%20on%20Malt%20Quality.%20Brewing%20Science%2064,%2022-31..pdf Table 2 of this study] for a lit of microbes that were found using traditional plating methods. * See this video presentation by Bart Lievens at the 2015 Belgian Brewers Conference: ::<youtube>5mttD027PMU</youtube>
==See Also==