Assessment of the microbial quality of ready-to-eat vegetable salads and berry fruit available on Polish market

Beata Kowalska

Department of Microbiology and Rhizosphere, The National Institute of Horticultural Research, Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland

Magdalena Szczech

Department of Microbiology and Rhizosphere, The National Institute of Horticultural Research, Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland


The consumption and sale of ready-to-eat products, i.e., fresh-cut vegetable salads and fruit, have been growing tremendously in the present time. Therefore, the microbial safety of such products is of great concern. In the current study, a survey of general microbiological contamination (mesophilic bacteria, yeasts, molds, Enterobacteriaceae, coli bacteria, Enterococcus, Lactobacillus, and Escherichia coli) of fresh-cut vegetable salads and berry-packed fruits available in Polish supermarket was undertaken.
In ready-to-eat salads, the high number of mesophilic bacteria ranged from 6.43 to 8.56 log10 cfu g–1, and also Enterobacteriaceae with mean value from 3.45 to 4.08 log10 cfu g–1 was detected. Mesophilic bacteria, yeast, and Enterobacteriaceae were detected in all salad samples. The molds were detected in 45% of salad samples, and their mean number ranged from 0.63 log10 cfu g–1 in salads with carrot or beetroot to 1.80 log10 cfu g–1 in salads with rocket.
Berry fruit was also heavily microbiologically contaminated. In particular, the means of mesophilic bacteria, molds, and yeasts were high. The number of molds detected in fruit samples, especially in raspberry samples, could be alarming. Enterobacteriaceae, Enterococcus, and coli bacteria were detected in a few samples of berry fruit. None of the ready-to-eat salads and fruit samples were contaminated by Escherichia coli.
Based on the tests that were conducted, it was found that the microbiological quality was not satisfactory. The findings suggest that following hygienic measures during processing and handling, the microbiological quality of vegetable salads and berry fruit available in Polish markets should be improved.


food safety, microbiological safety, microbiological contamination, bacteria, fungi, mold, ready-to-eat

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Beata Kowalska 
Department of Microbiology and Rhizosphere, The National Institute of Horticultural Research, Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland
Magdalena Szczech 
Department of Microbiology and Rhizosphere, The National Institute of Horticultural Research, Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland


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