As part of the master's thesis, we determined the content of biogenic amines (BA), gamma-aminobutanoic acid (GABA), the content of free amino groups and the antioxidant potential (AOP) of Mohant cheeses from different manufacturers. Using the HPLC method, after prior derivatization with dansyl chloride, the content of tryptamine, tyramine, putrescine, cadaverine, phenethylamine, histamine, agmatine, spermine, spermidine and GABA was determined immediately after purchase, after one month and after three months of storage. We also compared two series of cheeses that were produced in different seasons. We detected a relatively high BA content in individual cheese samples, with the exception of agmatine, spermine and spermidine, which were not specified in the analyzed samples. In general, we determined that cheeses greatly vary in the initial BA content, but the value of BA in each of the cheeses increases in accordance with the time of being stored. We did not find any differences in BA content in cheeses produced in the spring and summer. In the overall sum of all BA in the cheeses the most dominant were tyramine and putrescine (more than 120 mg/100 g), cadaveryne (more than 100 mg/100 g) and hystamine (48 mg/100 g). The content of amino groups in a gram of individual cheeses exceeded 300 μmol, which indicates a large extent of hydrolysis and the presence of short peptides, which give the cheese its characteristic bitter taste, that was confirmed by sensory analysis. The differences in values of AOP in the cheeses, determined with a DPPH method, were smaller compared to the differences in content of BA and free amino groups.
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