EFFECTS OF SUBSTRATE CONCENTRATION ON GROWTH AND LACTIC-ACID PRODUCTION BY MIXED CULTURES OF LACTOBACILLUS-BULGARICUS AND STREPTOCOCCUS-THERMOPHILUS

OZEN S., OZILGEN M.

JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY, vol.54, no.1, pp.57-61, 1992 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 54 Issue: 1
  • Publication Date: 1992
  • Doi Number: 10.1002/jctb.280540111
  • Journal Name: JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Agricultural & Environmental Science Database, Applied Science & Technology Source, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Computer & Applied Sciences, EMBASE, Food Science & Technology Abstracts, INSPEC, Metadex, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Page Numbers: pp.57-61
  • Keywords: MIXED CULTURES, MICROBIAL GROWTH, LACTIC ACID PRODUCTION, KINETICS, KINETICS, MICROORGANISMS, YOGURT
  • Middle East Technical University Affiliated: No

Abstract

The kinetics of growth and lactic acid production by mixed cultures of Lactobacillus bulgaricus and Streptococcus thermophilus were modeled with a set of modified logistic and Luedeking-Piret equations. The specific growth rates and the inhibitory effect of each individual species on the mixed culture growth were found to be determined by the media composition. The kinetic analysis clearly showed that the contribution of each microbial species to the mixed culture growth process changed drastically when the substrate concentration was about 15%. This optimum initial substrate concentration was in agreement with the results of the previous studies and the optimum found by trial and error procedure in commercial yogurt production.