FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY

Authors

IZABELA PODGÓRSKA, EWA SOLARSKA

Title

Assessment of microbiological quality of herbal teas in sachets

Abstract

The objective of the research study was to determine the microbial contamination of herbal teas in sachets available in the retail outlets in Lublin and the qualitative composition of mitosporic fungi occurring therein. The study involved 7 types of herbal teas from the following plants: lemon balm (Melissa officinalis), nettle, mint, fennel, linden, chamomile, and sage. Under the experiment, the following was determined: total number of bacteria, yeast, mitosporic fungi, and Escherichia coli bacteria; the analysis was performed to detect Salmonella and staphylococci coagulase (+). It was found that the total number of aerobic mesophilic bacteria, yeast, and mitosporic fungi ranged between: 103-106, 103-104, and 102-105 cfu·g-1, respectively. The herbal teas in sachets and containing nettle and mint showed the highest contamination by bacteria and mitosporic fungi, and those teas did not meet the microbiological purity requirements as set in the Polish Pharmacopoeia X. The qualitative composition of mitosporic fungi in the dried herbs tested varied; they all belonged to 10 species such as Alternaria, Aspergillus, Botrytis, Cladosporium, Fusarium, Mucor, Penicillium, Phoma, Rhizopus, and Trichoderma. In all the herbal tea samples tested, fungi of the genera: Aspergillus, Fusarium, and Penicillium prevailed. The sanitary/ hygienic condition of the nettle and mint tea raised major concerns for E. coli bacteria were detected therein at a level of 102 cfu·g-1. No Salmonella and staphylococci coagulase (+) were detected in the samples tested.

Keywords

dried herbs, microbiological quality, bacteria, yeast, mitosporic fungi

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