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updated "Ropy" section to include benefits of EPS for cell survivability
One study showed that the production of β-glucan coincided with the end of the growth phase of ''Pediococcus''. While small amounts of β-glucan were produced during growth, after 2 days of growth, β-glucan production increased as growth slowed. β-glucan production stopped when growth stopped. This study showed that β-glucan production is linked to ''Pediococcous'' growth, producing more towards the end of growth. This would explain why beer containing ''Pediococcus'' often goes ropy shortly after naturally carbonating in the bottle. This study found that other variables were not factors in the production of β-glucan, such differing levels of alcohol (although alcohol interacts with the β-glucan in a way that makes the viscosity seem thicker). The study also found that the lack of agitation increased the β-glucan production (wine makers will often agitate or aerate ropy wine to cure the wine from ropiness). A higher initial pH encourages higher growth (5.5+), which increases β-glucan production. A lower initial pH (3.5), decreases growth and β-glucan production. A higher concentration of glucose increased growth and β-glucan production. Glucose is needed for β-glucan production. While fructose alone is mostly insufficient, a combination of glucose and fructose was slightly more efficient than glucose alone <ref name="ESP"></ref>.
The presence of beta-glucans from barley have been observed to extend both the growth and the viability of ''Lactobacillus'' species in probiotics <ref>[http://www.mdpi.com/1422-0067/15/2/3025/htm Barley β-Glucans-Containing Food Enhances Probiotic Performances of Beneficial Bacteria. Mattia P. Arena, Graziano Caggianiello, Daniela Fiocco, Pasquale Russo, Michele Torelli, Giuseppe Spano, and Vittorio Capozzi. 2014.]</ref><ref>[http://www.mdpi.com/1422-0067/13/5/6026/htm Beta-Glucans Improve Growth, Viability and Colonization of Probiotic Microorganisms. Pasquale Russo, Paloma López, Vittorio Capozzi, Pilar Fernández de Palencia, María Teresa Dueñas, Giuseppe Spano, and Daniela Fiocco. 2012.]</ref>. One study looked at this effect in beta-glucans produced by ''Pediococcus parvulus'' and found that ''L. plantarum'' had a longer viability in a fermented medium with no additional food source when that medium was first fermented with ''P. parvulus'' and EPS was produced. The ''L. plantarum'' strain that was tested did not ferment the beta-glucans. This suggests that there is an interspecies simbiotic relationship between lactic acid bacteria that produce EPS and those that don't. The study also observed that more EPS was produced in an oat based wort and a rice based wort, while no EPS was produced in a barley based wort, suggesting that different food sources influence whether or not EPS is produced <ref>[http://www.mdpi.com/1422-0067/18/7/1588/htm In Situ β-Glucan Fortification of Cereal-Based Matrices by Pediococcus parvulus. Adrián Pérez-Ramos, María Luz Mohedano, Paloma López, Giuseppe Spano, Daniela Fiocco, Pasquale Russo, and Vittorio Capozzi. 2017.]</ref>.
It has been observed that ''Lactobacillus'' species can produce EPS (''Lactococcus lactis'', ''Lactobacillus delbrueckii'', ''Lactobacillus casei'', and ''Lactobacillus helveticus'') <ref name="ESP"></ref>.