Generation of aroma compounds in sourdough: Effects of stress exposure and lactobacilli-yeasts interactions

• Published in: Food microbiology Vol. 24; no. 2; pp. 139 - 148
• Main Authors: Guerzoni, M.E, Vernocchi, P, Ndagijimana, M, Gianotti, A, Lanciotti, R
• Format: Journal Article Conference Proceeding
• Language: English
• Published: London Elsevier 01.04.2007
• Subjects: acetic acid; alcohols; Alcohols - metabolism; Aldehydes - metabolism; bakers yeast; bakery industry; Biological and medical sciences; Bread - microbiology; Bread - standards; coculture; dough development; esters; Esters - metabolism; Fermentation; Food industries; Food Microbiology; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Hydrolases; lactic acid bacteria; Lactobacillus - metabolism; Lactobacillus - physiology; Lactobacillus sanfranciscensis; long chain fatty acids; microbial competition; odor compounds; Odorants - analysis; Osmosis; osmotic treatment; Oxidation-Reduction; Oxidative Stress; Saccharomyces cerevisiae; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae - physiology; sourdough; sourdough bread; volatile organic compounds; Volatilization; Volatile compound; Lactic acid bacteria; Yeast; Interaction; Microflora; Sourdough lactic acid bacteria; Stress; Sourdough yeasts; Microbiota interactions; Environmental stresses; Bacteria; Lactobacillaceae; Aroma; Volatile compounds; Lactobacillus
• ISSN: 0740-0020; 1095-9998
• DOI: 10.1016/j.fm.2006.07.007

The effects of the interaction between Saccharomyces cerevisiae LBS and Lactobacillus sanfranciscensis LSCE1 and of their responses to acid, oxidative or osmotic stress on alcohol and aroma production were assessed. The exposure of S. cerevisiae LBS and L. sanfranciscensis LSCE1 cells to oxidative, acid or osmotic sub-lethal stress gave rise to a common or specific responses. γ-decalactone, 2(5H)-furanones and aldehydes were overproduced by LAB following oxidative stress. The acid stress induced both in yeasts and LAB, as well as in their co-cultures, a relevant accumulation of isovaleric and acetic acids and higher alcohols. A cross-exposure of yeasts and LAB to their preconditioned media, generated in S. cerevisiae a release of esters including esters of long-chain unsaturated fatty acids coming from membrane phospholipids. These esters were excreted also by yeasts following a pressure stress.