Characterization of the growth of Lactobacillus plantarum in milk in dependence on temperature

The effect of temperature on the growth dynamics of Lactobacillus plantarum in the model environment of UHT milk was investigated. Based on the experiments between temperatures ranged from 8 to 40 °C, growth dynamics of the studied isolate was positively determined by the cultivation temperature that led to increasing intensity of growth in the exponential phase (except for temperatures 38 and 40 °C). Final counts in stationary phase have reached concentrations about 10⁷ CFU · ml⁻¹ from initial 10³ CFU · ml⁻¹, except for marginal 8 and 40 °C. Experimentally, it was found, that optimal temperature was close to 37 °C, where the fastest specific growth rate in an exponential phase was recorded (μ = 0.7683 h⁻¹, t_d = 54 min) and the stationary phase was reached after 24 h of incubation. During the growth and multiplication of Lb. plantarum, no significant decrease of pH values in comparison to initial ones in dependence on temperature were determined (0.00—0.24 units).