Journal of Applied Microbiology, Vol.126, No.5, 1468-1479, 2019
Influence of culture conditions on the technological properties of Carnobacterium maltaromaticum CNCM I-3298 starters
Aim The aim of this study is to investigate the effect of a broad spectrum of culture conditions on the acidification activity and viability of Carnobacterium maltaromaticum CNCM I-3298, the main technological properties that determine the shelf-life of biological time-temperature integrator (TTI) labels. Methods and Results Cells were cultivated at different temperatures (20-37 degrees C) and pH (6-9 center dot 5) according to a modified central composite design and harvested at increasing times up to 10 h of stationary phase. Acidification activity and viability of freeze-thawed concentrates were assessed in medium mimicking the biological label. Acidification activity was influenced by all three culture conditions, but pH and harvest time were the most influential. Viability was not significantly affected by the tested range of culture conditions. Conclusions Carnobacterium maltaromaticum CNCM I-3298 must be cultivated at 20 degrees C, pH 6 and harvested at the beginning of stationary phase to exhibit fastest acidification activities. However, if slower acidification activities are pursued, the recommended culture conditions are 30 degrees C, pH 9 center dot 5 and a harvest time between 4-6 h of stationary phase. Significance and Impact of the Study Quantifying the impact of fermentation temperature, pH and harvest time has led to a predictive model for the production of biological TTI covering a broad range of shelf-lives.