Bactericidal effect of different populations of Lactobacillus casei var. rhamnosus on Escherichia coli ATCC 25922TM inoculated on Buttery cheese produced in laboratory conditions during the storage

Abstract

This article aims to determine the bactericidal effect of Lactobacillus casei var. rhamosus on E. coli on Buttery cheese made under laboratory conditions. For which the counting method was used in plaque and the results expressed as UFC/g.

They worked three trials problem and one control, where it was added to the buttery cheese at the stage of initial mixing three separate populations of Lactobacillus casei var. Rhamnosus (103, 106 and 109 UFC/mL) on an initial population of Escherichia coli ATCC 25922 (103 UFC/mL) in each test problem, while control group only an initial population of Escherichia coli ATCC 25922 was inoculated (103 CFU/mL). Samples were stored at a temperature of 8 ± 2 °C for 15 days.

The method of bacterial plate count envisioned that the initial population of 109 UFC/mL of Lactobacillus casei var.Rhamnosus added to the Buttery cheese at the stage of mixing, exerted a bactericidal effect on the population 103 UFC/mL E. coli since which it reduced the bacteria to a population of 10 UFC/g on day 15 of the investigation.