Protective effects of Lactobacillus cultures in Dutch-type cheese-like products

- Probiotic strains of Lactobacillus sp. inhibit the growth of technologically harmful microflora.
- Protective effects are influenced by ripening and storage temperature.
- Antibacterial activity varies subject to the applied bacterial culture.

The aim of this study was to determine the influence of probiotic cultures, Lactobacillus paracasei LPC37, Lactobacillus acidophilus NCFM and Lactobacillus rhamnosus HN001, on changes in the average counts of starter cultures and technologically harmful microflora (coliform bacteria, Enterococcus sp., yeasts and molds, Clostrudium perfringens, Clostridium tyrobutiricum) isolated from Dutch-type cheese-like products. The population size of starter cultures in experimental cheese-like products was not determined by Lactobacillus sp. counts. The counts of mesophilic citrate-fermenting bacteria were significantly lower in cheese-like products containing L. acidophilus NCFM. Lactobacillus sp. did not induce (P > 0.05) changes in Enterococcus sp. counts in cheese-like products during ripening. The average population size of coliform bacteria, yeasts and molds was significantly influenced by Lactobacillus sp. counts and processing temperature. Cl. perfringens counts were higher in experimental than in control products during ripening. An inverse relationship was observed during storage. All control and experimental cheese-like products were free of Cl. tyrobutiricum.The use of heterofermentative Lactobacillus sp. cultures in the production of ripened Dutch-type cheese-like products reduces the populations of technologically harmful microorganisms that compromise the quality, storage stability and safety of end products.