Background. Microorganisms not only cause changes of food quality, but also synthesize toxic compounds, which contaminate food products. In order to avoid contamination by microscopic fungi during processing and to ensure the quality of processed food products, effective preparations for cleaning of work surfaces are created and used.
The aim of the work was to test the effectiveness of new imported detergents for suppression of growth of microscopic fungi, yeasts and bacteria detectable on food products and in manufacturing environment.
Material and methods. The object of the investigation included 4 micromycetes: Penicillium frequentans, Aspergillus niger, Rhizopus oryzae, Alternaria alternata; 4 yeasts: Saccharomyces cerevisiae, Candida glabrata, Candida lipolytica, Rhodotorula rubra; 4 bacteria: Pseudomonas aeruginosa, Streptococcus aureus, Bacillus mycoides, Escherichia coli.
Micromycetes and yeasts were grown on malt agar, whereas bacteria - on nutrient agar. Microorganism spore suspension was used at 106/ml concentration. Microorganism susceptibility was tested using paper discs, which were moistened with a detergent of the appropriate concentration. The diameter of sterile zones around discs was measured in millimetres, and basing on this, microorganism susceptibility was evaluated.
Results. It was found that detergent “Pesetti antibact” 0.4 and 0.6% mostly inhibited growth of bacteria. The large sterile zones for Bacillus mycoides was detected under intluence of both detergent concentrations (bacteria grew only on the edge of the dish); the sterile zones of Streptococcus aureus were 12.6+2.1 and 12.7+0.57 mm. Growth of all yeasts was in flu enced by de ter gent “F261 Kloriitti-Forte”. The largest sterile zones were detected after cultivation of Saccharomyces cerevisiae (15±3.4 and 15.3±0.57 mm) and Rhodotorula rubra (11.6±0.57 mm). Detergent “Pesetti antibact” 0.6% was more effective against Saccharomyces cerevisiae (15±1.7 mm) and Candida glabrata (15.3±4 mm).
It was found that growth of Alternaria alternata was mostly influenced of all used detergents. The large sterile zones of this micromycete were detected under influence of “F261 Kloriitti-Forte”, less - under influence of “Potassium sorbate” (20±1,4 and 26±5,6 mm).
Conclusions. Growth of bacteria Streptococcus aureus, Bacillus mycoides was the most influenced by “Pesetti antibact” 0.4 and 0.6%. The largest sterile zones of yeasts Saccharomyces cerevisiae, Rhodotorula rubra were detected under influence of “F261 Kloriitti-Forte” and “Pesetti antibact”. Growth of Alternaria alternata was mostly influenced of all used detergents. The largest sterile zones of this micromycete were detected under influence of “F261 Kloriitti-Forte”; micromycete grew only on the edge of the dish.
