Out of six samples of wastewater produced in the dairy industry, taken in 2017 at various places of dairy operations, 86 bacterial strains showing decarboxylase activity were isolated. From the wastewater samples, the species of genera Staphylococcus, Lactococcus, Enterococcus, Microbacterium, Kocuria, Acinetobacter, Pseudomonas, Aeromonas, Klebsiella and Enterobacter were identified by the MALDI-TOF MS and biochemical methods. The in vitro produced quantity of eight biogenic amines (BAs) was detected by the HPLC/UV–Vis method. All the isolated bacteria were able to produce four to eight BAs. Tyramine, putrescine and cadaverine belonged to the most frequently produced BAs. Of the isolated bacteria, 41% were able to produce BAs in amounts >100 mg L−1. Therefore, wastewater embodies a potential vector of transmission of decarboxylase positive microorganisms, which should be taken into consideration in hazard analyses within foodstuff safety control. The parameters of this wastewater (contents of nitrites, nitrates, phosphates, and proteins) were also monitored.

Inorganic selenium, the most common form of harmful selenium in the environment, can be determined using electrochemical sensors which are compact, fast, reliable and easy-to-operate devices. Despite the progress in...

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The aim of this work was to evaluate microbial quality and the presence of biogenic amines in raw bars. This study was focused on microbiological research in order to determine the presence of selected indicator groups of microorganisms depending on the composition of raw food. Identification of microorganisms was carried out by MALDI-TOF MS. In the second part of the experiment, biogenic amines and polyamines were analyzed using high performance liquid chromatography with UV/VIS detection. An increased incidence of mold has been reported in the samples, which is associated with a risk of mycotoxin production. After identifying microorganisms, it was found out that genera Micrococcus, Bacillus and Staphylococcus were the most represented. The highest concentration of biogenic amines (tyramine 42.2 ±4.8 mg.kg-1; putrescine 54.0 ±2.9 mg.kg-1) was found in a sample containing the vegetable component. The average concentration of biogenic amines in the tested raw bars was <30 mg.kg-1 and therefore they do not pose a serious health hazard to a consumer.