Interactions Between Lactococcus lactis subsp. lactis and Issatchenkia orientalis at Milk Fermentation

Elise Borregaard, Nils Arneborg

Department of Dairy and Food Science, The Royal Veterinary and Agricultural University, Rolighedsvej 30, DK-1958 Frederiksberg C, Denmark

Article history:
Received September 10, 1997
Accepted January 15, 1998

Key words:
interactions, fermentation, Lactococcus lactis subsp, lactis, Issatchenkia orientalis, milk

Summary:
Growth, substrate utilization, and product formation during growth of Lactococcus lactis subsp. lactis and Issatchenkia orientalis as single cultures and as a mixed culture in reconstituted skim milk were measured in order to delect interactions between the two microorganisms in fermented milk. As lo substrate utilization, no interactions could be detected. L. lactis slightly stimulated the growth of I. orientalis. I. orientalis slightly decreased the acidification of the growth medium by L. lactis. In addition, the lactic acid, acetic acid, acelaldehyde, and acetoin concentrations in the growth medium were significantly decreased, when L. lactis was grown in the presence of I. orientalis.