Kinetic analysis and mathematical modeling of growth parameters of Lactobacillus plantarum in protein-rich isolates from tomato seed

The aim of the present study was to evaluate the applicability of using protein-rich isolates from tomato seed as a sole source of nutrition for the growth of lactic acid bacteria. Unstructured mathematical and logistic models were proposed to describe growth, pH drop, lactic acid production and nutriment consumption by Lactobacillus plantarum in whole and defatted isolates in order to compare their suitability for the production of a fermented beverage. These media have considerable good quantities of nutriment that allowed the growth of L. plantarum, after which the cell numbers begin to decline. The maximum biomass was observed in defatted isolate (1.42 g L⁻¹) followed by the whole isolate (1.24 g L⁻¹). The lactic acid increased by about 5.5 and 6.5 times respectively in whole and defatted protein isolates. However, significant nutriment consumption occurred during the growth phase as well as stationary phase. A reduction of 61.90% and 95.88% in sugar content, as well as 21.91% and 16.93% reduction in protein content were observed respectively in whole and defatted isolates. In most cases, the proposed models adequately describe the biochemical changes taking place during fermentation and are a promising approach for the formulation of tomato seed-based functional foods.