Isovaleric acid is mainly produced by Propionibacterium freudenreichii in Swiss cheese

Anne Thierry (1) , Romain Richoux (2) , Jean-René Kerjean (3)

1 STLO - Science et Technologie du Lait et de l'Oeuf
2 Institut Technique Français des Fromages Rennes
3 ITFF - Institut Technique Français des Fromages

Isovaleric acid (3-methylbutyric acid) and 2-methylbutyric acid contribute to Swiss cheese flavour. In order to determine the contribution of propionibacteria (PAB) to the production of methylbutyric acids, mini-Swiss cheeses were manufactured with or without PAB as a secondary starter (25 Propionibacterium freudenreichii strains), associated with different cultures of thermophilic lactic starters. In the presence of PAB, the quantity of methylbutyric acids was three to ten times greater, depending on PAB strain, than in the absence of PAB, regardless of the species and the strain of lactobacilli used (20–63 vs. o6mgkg 1 ripened cheese). PAB produced methylbutyric acids concomitantly with acetic and propionic acids, then kept on producing methylbutyric acids after propionic fermentation. The increase in salt-in-moisture content of cheese from 1.0% to 1.8% induced a strain-dependent inhibition of isovaleric acid production. This study shows that P. freudenreichii is the main contributor to methylbutyric acid production in Swiss cheese.

Mots clés: cheesemaking; isovaleric acid; yeast; swiss cheese; technologie fromagère; sel; arôme; levure thermophile; propionibacterium frudenreichii; fromage suisse; acide isovalérique

Mots clés: acide iso valérique; levure; propionibacterium freudenreichii

Domaines: Microbiologie et Parasitologie; Alimentation et Nutrition; Ingénierie des aliments

Anne Thierry, Romain Richoux, Jean-René Kerjean. Isovaleric acid is mainly produced by Propionibacterium freudenreichii in Swiss cheese. International Dairy Journal, 2004, 14 (9), pp.801-807. ⟨10.1016/j.idairyj.2004.02.002⟩. ⟨hal-02264923⟩