The aim of this study was to evaluate suitability of legumes as carriers for probiotic strain Lactobacillus rhamnosus GG, leading to the development of new probiotic foods for consumers who have to restrict or dislike dairy products. The growth and metabolic activity of the probiotic strain Lactobacillus rhamnosus GG during fermentation of waterbased leguminous porridges, prepared from soy bean, soy flour, green lentil, husked lentil, white bean, speckled bean, red bean, yellow pea, chickpea, and chickpea flour, were monitored. Viable cell counts, pH values, and contents of organic acids were analysed during static fermentation of autoclaved substrates at 37 °C for 48 h. Lactobacillus rhamnosus GG was able to grow up to the counts higher than 6 log CFU g–1 (measured values in the range of 7.8–8.9 log CFU g–1), which is legislative limit for labelling food as probiotic. pH values of fermented substrates varied between 4.0–6.0, concentration of lactic acid ranged from 99.9 to 687.7 mg kg–1, and level of acetic acid varied from 266.1 to 1182.0 mg kg–1.
Environmental factors, including temperature and nutrient composition, have considerable impact on the growth dynamic of each microbial species; moreover it is strongly dependent on the selected strain. Therefore, the aim of this study was to describe and analyse the growth dynamics of the strain Lactobacillus acidophilus NCFM (Howaru) by predictive microbiology tools. The intensity of Lb. acidophilus NCFM growth in MRS broth and in milk was significantly affected by the incubation temperature described by the Gibson’s model, from which the optimal temperature for the Lb. acidophilus growth of 40.5 °C in MRS broth and 40.1 °C in milk was calculated. These cardinal temperatures were verified with the CTMI model providing also other cardinal (minimal Tmin, maximal Tmax, and optimal Topt) values for Lb. acidophilus NCFM growth Topt=40.2 °C, Tmin=15.4 °C, Tmax=46.0 °C and Topt=40.3 °C, Tmin=14.3 °C, Tmax=46.6 °C in MRS broth and in milk, respectively.