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Lebleux et al. (2019) measured biofilm density for 12 strains across 5 of the genetic groups of ''B. bruxellensis''. All of the strains produced a biofilm when in contact with a surface (polystyrene and stainless steel, in the case of this study), and the thickness of the biofilm was proportional to the cell size of each strain. The biofilms contained filamentous cells that started from the base of the biofilm and extended upward, indicating multiple layers. The biofilms also contained exopolysaccharides (EPS), but the makeup of the EPS was not analyzed and this was identified as a goal for further study. The average thickness was only 9.45 µm which is much thinner than other biofilm-forming yeast species (''Candida'' and a biofilm-producing strain of ''S. cerevisiae'' <ref>[https://bmcmicrobiol.biomedcentral.com/articles/10.1186/s12866-014-0305-4 Saccharomyces cerevisiae biofilm tolerance towards systemic antifungals depends on growth phase. Bojsen, R., Regenberg, B. & Folkesson, A. BMC Microbiol 14, 305 (2014). DOI: 10.1186/s12866-014-0305-4.]</ref>). They found that one or two strains were less dense (contained fewer cells) than the average. A couple of the strains grew a biofilm a little slower than average. Two of the strains in biofilm form were added to wine; each of the biofilms released cells into the wine, although one strain released more cells than the other. Introduction to the wine first led to cell death for some cells due to the harsh environment of the wine, but after several days the ''B. bruxellensis'' strains began to re-grow in the wine. It was observed that for one of the strains, the cells appeared larger than normal, round, and had thicker cell walls, possibly forming what is known as [https://en.wikipedia.org/wiki/Chlamydospore chlamydospore cell structures]. It was not confirmed in the study whether these cells were actually chlamydospores, and their structure could be due to relatively insignificant reasons <ref name="heit_lebleux" />. Chlamydospore cell structures are known to help certain species of non-yeast fungi survive harsh environments; however, it has not yet been established that yeast with chlamydospore cell structures helps them survive harsh conditions, and this was also identified in the study as an area for further research <ref name="Lebleux_2019" />.

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