Lait 67 (1987) 41-50
DOI: 10.1051/lait:198712

Influence de quatre milieux de propagation sur le comportement de six levains lactiques mésophiles du commerce

Renée ROY^a, J. GOULET^a and P. PROVENCHER<sup>b

a</sup>  Département de Sciences et Technologie des Aliments et Centre de Recherche en Nutrition Université Laval, Québec, Canada G1K 7P4
^b  Service des Maladies infectieuses, Centre Hospitalier de l'Université Laval Sainte-Foy, Québec, Canada G1K 7P4

Abstract - Effect of propagation media on the growth and acid production of starter cultures for cheese making
The growth and acid production of six cheddar cheese starter cultures were studied in four propagation media: two heat treated (Lo Heat and Hi Heat) commercial non fat dry milks (NFDM) and two phage-inhibitory media (Nulac and One-2-One).
Highly significant differences in growth and acid production were obtained between NFDM and phage-inhibitory media during propagation; these differences were much less significant upon further transfer into fresh fluid milk (simulated cheese production).
Phage-inhibitory media appeared to enhance the proteolytic activity of most starter cultures under study; this effect did not persist however in the first stage (4 h) of a simulated cheese production.

Résumé - Nous avons comparé la performance de six levains lactiques commerciaux dans quatre milieux de propagation : poudres de lait écrémé Lo Heat et Hi Heat et deux milieux phosphatés inhibiteurs de phages. La nature des milieux de culture a influencé le comportement des cultures lactiques en fabrication fromagère simulée. Les différences observées entre les divers milieux sont à l'avantage des poudres Lo Heat et Hi Heat.

Key words: Starters / Skim milk powder / Phage-inhibitory media

Mots clés : Levain / Lait écrémé en poudre / Milieux phosphatés inhibiteurs de phages