title: Sourdough microbial community dynamics: An analysis during French organic bread-making processes.
abstract: Natural sourdoughs are commonly used in bread-making processes, especially for organic bread. Despite its role in bread flavor and dough rise, the stability of the sourdough microbial community during and between bread-making processes is debated. We investigated the dynamics of lactic acid bacteria (LAB) and yeast communities in traditional organic sourdoughs of five French bakeries during the bread-making process and several months apart using classical and molecular microbiology techniques. Sourdoughs were sampled at four steps of the bread-making process with repetition. The analysis of microbial density over 68 sourdough/dough samples revealed that both LAB and yeast counts changed along the bread-making process and between bread-making runs. The species composition was less variable. A total of six LAB and nine yeast species was identified from 520 and 1675 isolates, respectively. The dominant LAB species was Lactobacillus sanfranciscensis, found for all bakeries and each bread-making run. The dominant yeast species changed only once between bread-making processes but differed between bakeries. They mostly belonged to the Kazachstania clade. Overall, this study highlights the change of population density within the bread-making process and between bread-making runs and the relative stability of the sourdough species community during bread-making process.
authors.affiliation: LUNAM Université Oniris, Laboratoire de Microbiologie Alimentaire et Industrielle, rue de la Géraudière, 44000 Nantes Cedex 3, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Lhomme
authors.affiliation: INRA, UMR 0320/UMR 8120 Génétique Végétale, F-91190 Gif-sur-Yvette, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Urien
authors.affiliation: Univ Paris-Sud, UMR 0320/UMR 8120 Génétique Végétale, F-91190 Gif-sur-Yvette, France.
authors.forename: Judith
authors.initials: J
authors.lastname: Legrand
authors.affiliation: LUNAM Université ONIRIS, UMR INRA 1014 Secalim, rue de la Géraudière, BP 88225 Nantes Cedex 3, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Dousset
authors.affiliation: LUNAM Université Oniris, Laboratoire de Microbiologie Alimentaire et Industrielle, rue de la Géraudière, 44000 Nantes Cedex 3, France. Electronic address: bernard.onno@oniris-nantes.fr.
authors.forename: Bernard
authors.initials: B
authors.lastname: Onno
authors.affiliation: Univ Paris-Sud, UMR 0320/UMR 8120 Génétique Végétale, F-91190 Gif-sur-Yvette, France; INRA, UMR 1083 Sciences pour l'œnologie, 34060 Montpellier Cedex 2, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Sicard
mesh_terms: D001939:Bread / Q000382:microbiology*; D015169:Colony Count, Microbial; D005285:Fermentation; D005516:Food Microbiology; D058870:Food, Organic / Q000382:microbiology; D007778:Lactobacillus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D059013:Microbial Consortia / Q000502:physiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014908:Triticum / Q000382:microbiology; D015003:Yeasts / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D012336:RNA, Ribosomal, 16S
keywords: Kazachstania sp.; Lactic acid bacteria; Lactobacillus sanfranciscensis; Saccharomyces sp.; Yeast