Changes

Some strains of ''Pediococcus pentocaseus'' have been found to produce bacteriocins, which are toxins that are produced by the cells that inhibit the growth of other types of bacteria. For example, Bootleg Biology's "Sour Weapon" culture produces antimicrobials called bacteriocins or pediocins (see Bootleg Biology's [https://www.facebook.com/BootlegBiology/photos/a.148869931970401.1073741829.124634287727299/465185997005458/?type=1&theater Facebook post] regarding bacteriocins for more info). These can inhibit and kill similar species of bacteria like ''Lactobacillus'' and other ''Pediococcus'' species in mixed-culture fermentations. Bacteriocin production can be higher when ''Pediococcus pentocaseus'' is co-fermented with other bacteria than when it is fermented on its own <ref>[https://www.frontiersin.org/articles/10.3389/fmicb.2018.02952/abstract Enhanced Bacteriocin Production by Pediococcus pentosaceus 147 in Co-Culture with Lactobacillus plantarum LE27 on Cheese Whey Broth. Carolina Gutiérrez-Cortés, Héctor Suarez, Gustavo Buitrago, Luis A. Nero and Svetoslav D. Todorov. 2018. DOI: 10.3389/fmicb.2018.02952.]</ref>. A strain of ''Pediococcus pentocaseus'' was found to produce a "class II" enteriocin that inhibits the growth of ''E. coli'' and ''Staphylococcus aureus'' <ref>[https://www.sciencedirect.com/science/article/pii/S0882401017314559 Antibacterial activity of Lactobacillus plantarum isolated from Tibetan yaks. Lei Wang, Hui Zhang, Mujeeb Ur Rehman, Khalid Mehmood, Xiong Jiang, Mujahid Iqbal, Xiaole Tong, Xing Gao, Jiakui Li. 2017.]</ref>. ''P. damnosus'' also produces an antimicrobial compound called pediocin PD-1, which can inhibit several bacteria spp including ''O. oeni'' <ref>[http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2672.2001.01486.x/full Growth optimization of Pediococcus damnosus NCFB 1832 and the influence of pH and nutrients on the production of pediocin PD-1. H.A. Nel1, R. Bauer, E.J. Vandamme and L.M.T. Dicks. Jan 2002.]</ref><ref>[http://www.ncbi.nlm.nih.gov/pubmed/15878403 Purification, partial amino acid sequence and mode of action of pediocin PD-1, a bacteriocin produced by Pediococcus damnosus NCFB 1832. Bauer R, Chikindas ML, Dicks LM. May 2005.]</ref>.

''P. damnosus'' can produce high amounts of diacetyl during lactic acid production <ref>[http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2672.2000.00956.x/pdf Identification of pediococci by ribotyping. R. Satokari, T. Mattila-Sandholm and M.L. Suihko. Journal of Applied Microbiology 2000, 88, 260–265.]</ref><ref>[http://mmbr.asm.org/content/77/2/157.full The Microbiology of Malting and Brewing. Nicholas A. Bokulicha, and Charles W. Bamforth. June 2013.]</ref>. ''P. damnosus'' also produces an antimicrobial compound called pediocin PD-1, which can inhibit several bacteria spp including ''O. oeni'' <ref>[http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2672.2001.01486.x/full Growth optimization of Pediococcus damnosus NCFB 1832 and the influence of pH and nutrients on the production of pediocin PD-1. H.A. Nel1, R. Bauer, E.J. Vandamme and L.M.T. Dicks. Jan 2002.]</ref><ref>[http://www.ncbi.nlm.nih.gov/pubmed/15878403 Purification, partial amino acid sequence and mode of action of pediocin PD-1, a bacteriocin produced by Pediococcus damnosus NCFB 1832. Bauer R, Chikindas ML, Dicks LM. May 2005.]</ref>. ''P. claussenii'' tends to produce a smaller amount of acetic acid than lactic acid in about a 1:3 ratio. ''P. damnosus'' tends to produce only lactic acid and no acetic acid <ref name="Geissler">[http://www.sciencedirect.com/science/article/pii/S0168160515301033 Metabolic strategies of beer spoilage lactic acid bacteria in beer. Andreas J. Geissler, Jürgen Behr, Kristina von Kamp, Rudi F. Vogel. 2015.]</ref>, although some strains have been found to produce small amounts of acetic acid of around 100-300 ppm. This level is slightly below and above flavor thresholds in lager beer (but could be additive with other organisms) <ref>[http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.2010.tb00393.x/abstract Isolation, Identification, and Characterisation of Beer-Spoilage Lactic Acid Bacteria from Microbrewed Beer from Victoria, Australia. Garry Menz, Christian Andrighetto, Angiolella Lombardi, Viviana Corich, Peter Aldred, Frank Vriesekoop. 2010.]</ref>, but significantly less than the total acetic acid often found in gueuze (around 700-2200 ppm <ref>[http://www.horscategoriebrewing.com/2016/07/duivelsbier-of-halle.html Jansen, Dave. Hors Category Blog. "Duivelsbier of Halle". 07/30/2016. Retrieved 01/31/2018.]</ref>) and Flanders reds (300-2300 ppm <ref>[http://www.sciencedirect.com/science/article/pii/S0168160515301896 Microbial diversity and metabolite composition of Belgian red-brown acidic ales. Isabel Snauwaert, Sanne P. Roels, Filip Van Nieuwerburg, Anita Van Landschoot, Luc De Vuyst, Peter Vandamme. 2015.]</ref>). ''Pediococcus'' also carry the decarboxylase enzyme (PAD) which converts hydroxycinnamic acid (ferulic acid) into phenols (4-vinyl guaiacol) <ref name="lentz_2018">[http://www.mdpi.com/2311-5637/4/1/20/html#B13-fermentation-04-00020 The Impact of Simple Phenolic Compounds on Beer Aroma and Flavor. Michael Lentz. 2018. doi: 10.3390/fermentation4010020.]</ref>