Purpose: The objective is to evaluate the antimicrobial efficacy of fermentation-based cultured sugar product Verdad F95 against in low pH model beverage system.
Methods: Model low pH broth was prepared using water, sucrose, apple juice concentrate, and an acidifier. Candida albicans cells, Fusarium oxysporum and Aspergillus niger spores were independently inoculated to have ca. 2-3 log CFU/ml counts in the model system with pH of 3.2. Treatments with Verdad F95 from 0-2% in 10 equal concentration steps were prepared. The inoculated samples were stored at room temperature ca. 20 °C for 20 days, respectively, for optical density measurement. All the treatments were done multiple samples (n = 5). The yeast growth was measured using OD measurement at 595 nm and mold growth was evaluated using visual examination.
Results: The C. albicans experimental data indicate that at minimum use level of 1.0% cultured sugar, the yeast growth was inhibited throughout the incubation period, keeping the OD value less than 0.1. The F. oxysporum and A. niger growth data indicates that 1.0% cultured sugar inhibited the mold growth throughout the incubation period (P < 0.05).
Significance: This research substantiates the excellent antimicrobial efficacy of natural antimicrobial, cultured sugar, against spoilage micro-organisms in model system. This research also provides food industry with a potential antimicrobial to replace current chemical preservatives.