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''Pediococcus'' species and strains are generally resistant to hop compounds, and have been reported to grow in beer with at least 30 IBU <ref name="Geissler"></ref>. It has been suggested by research that horizontal gene transfer (transfer of genetic material by means other than reproduction) allows ''Pediococcus'' species (and other LAB) to obtain the genes associated with resistance to hops (primarily multi-drug transporter "horA", along with "hitA" or "horC"). This has been thought to allow ''Pediococcus'' to adapt to living in beer <ref name="Snauwaert"></ref>.
While able to grow in the presence of hops, the presence of hops still inhibits ''P. damnosus''. For example, one study found that in the presence of 15 IBU, lactic acid production was reduced by ~82%. Exposure to 15 IBU also increased diacetyl production by 350%, while 2,3-pentanedione (buttery, nutty, toasted, caramellic, diacetyl and acetoin notes <ref>[http://www.thegoodscentscompany.com/data/rw1003991.html "acetyl propionyl ". The Good Scents Company. Retrieved 01/18/2017.]</ref> ) was decreased by 25%. Interestingly, exposure to 3% ABV and no hops reduced the production of diacetyl and 2,3-pentanedione by about 20%. The addition of vitamins, specifically thiamine and riboflavin, increased the production of lactic acid in the presence of 15 IBU or no hops by about 15-30%. However, thiamine also increased diacetyl production by 100-125% and 2,3-pentadione production by 20-30% without the presence of hops. In the presence of 15 IBU, thiamine and/or riboflavin increased diacetyl production by about 26-36% and 2,3-pentadione by about 40-114% <ref>[http://onlinelibrary.wiley.com/doi/10.1002/jib.385/full The influence of thiamine and riboflavin on various spoilage microorganisms commonly found in beer. Barry Hucker, Melinda Christophersen, Frank Vriesekoop. 2017.]</ref>.
==Storage==