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Microbial contamination of fruit teas
Kuřáková, Hana ; Popelářová, Eva (advisor) ; Killer, Jiří (referee)
Teas are consumed daily by millions of people on the World, therefor it is important to care for their microbial harmlessness.
The aim of this work was to conduct a reaserch in regards to general information about fruit teas, their manufacturing and possibilities of contamination by undesirable microorganisms. In this research were also described important bacteria and fungii and we focused on mycotoxins and the elimination of microorganisms from a food.
Representation of microorganisms in teabags was evaluated in practical part of this research. We focused on total quantity of microorganisms, coliform bacteria, that can be pathogenic in higher representation and micromycetes. Genus structure of micromycetes was important in particular, because they can produce metabolites, mycotoxins, that can be a cause for many diseases.
Analyses were conducted by two methods. Variant classified as A was consisting of transformation of the teabag contents into the physiological solution. Variant classified as B was consisting of watering of the teabag contents. During evaluation, both of these variants were compared.
From the results of this work it was found out, that quantities of microorganisms were relativem small. It was discovered, that during the sample preparation by watering the sample with boiling water (variant B) the quantity of microorganisms will lower, in some cases they were not present at all. The presence of wider genera of micromycetes was also discovered. Three genera were dominant Aspergillus, Penicillum and Cladosporium. These free found of genera can be dangerous, because of mycotoxins, however micromytes in variant B were only represented by genera Cladosporium and Penicillum and in small measure.
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