Effects of Proteus vulgaris growth on the establishment of a cheese microbial community and on the production of volatile aroma compounds in a model cheese

Abstract

Aims: To investigate the impact of Proteus vulgaris growth on a multispecies ecosystem and on volatile aroma compound production during cheese ripening. Methods and Results: The microbial community dynamics and the production of volatile aroma compounds of a nine‐species cheese ecosystem were compared with or without the presence of P. vulgaris in the initial inoculum. Proteus vulgaris was able to colonize the cheese surface and it was one of the dominant species, representing 37% of total isolates at the end of ripening with counts of 9·2 log10 CFU g−1. In the presence of P. vulgaris, counts of Arthrobacter arilaitensis, Brevibacterium aurantiacum and Hafnia alvei significantly decreased. Proteus vulgaris influenced the production of total volatile aroma compounds with branched‐chain aldehydes and their corresponding alcohols being most abundant. Conclusions: Proteus vulgaris was able to successfully implant itself in a complex cheese ecosystem and significantly contributed to the organoleptic properties of cheese during ripening. This bacterium also interacted negatively with other bacteria in the ecosystem studied. Significance and Impact of the Study: This is the first time that the impact of a Gram‐negative bacterium on cheese microbial ecology and functionality has been described.

Isolation and Identification of the Microbiota of Danish Farmhouse and Industrially Produced Surface-Ripened Cheeses

“…First, the Gram-negative bacterial microbiota was associated with hygienic problems, but more recently an interest in their role in flavour production has been reported [11]. In the present study, a significant Gram-negative bacterial microbiota consisting of Proteus vulgaris and Alcaligenes faecalis was found on cheese from dairy C. A previous study has focused on P .…”

“…The presence of Gram-negative bacteria was first hypothesised to be indicative of hygienic problems. However, more recent results have shown that they produce important cheese flavour compounds and thus might contribute positively to the cheese ripening process [11]. Several studies have characterised the cheese microbiota by both culture-dependent methods and -independent methods [43].…”

Yarrowia lipolytica: Safety assessment of an oleaginous yeast with a great industrial potential

“…In some of the studies, the synergistic effects of Y. lipolytica with other microorganisms and, in particular, with D. hansenii have been stressed (De Wit et al, 2005;Freitas et al, 1999;Wyder et al, 1999). Finally, Y. lipolytica is repeatedly included in complex, experimental cheese communities containing multiple bacterial, fungal and yeast species (Deetae et al, 2009;DelbesPaus et al, 2012;Irlinger et al, 2012;Martin et al, 2001). …”

Microbial composition of defect smear – A problem evolving during foil-prepacked storage of red-smear cheeses

“…Propionibacterium spp., in particular P. freudenreichii are known as an exopolysaccharide producer (Deutsch, Falentin, Dols-Lafargue, LaPointe, & Roy, 2008) that therefore can contribute to smearyness of the cheese surface and to off-flavor due to propionate production as well as to blowing of the foil-package through gas formation. P. vulgaris is a Gramnegative opportunistic pathogen with swarming ability and a potential contributor to off-flavor due to indole production and its potential to produce volatile compounds in large variety (Deetae, Bonnarme, Spinnler, & Helinck, 2007;Deetae et al, 2009).…”