In the scope of this master's thesis, we determined the content of γ-amino butanoic acid (GABA), biogenic amines (BA) and free amino acids (AAs) in canned fish during the production process and in canned fish on the market. Lysine, alanine and tyrosine are the main AAs present in fish. We divided the products from the market into three groups: fish, fish pate and fish with vegetables. The content of GABA, BA and AAs varied between the groups. The GABA content is the highest in fish pates (8632.12 nmol/g), while the concentration in fish with vegetables is 4097.43 nmol/g, and in the fish group it is 21.49 nmol/g. The addition of fermented vegetables contributed to higher values of GABA, agmatine, spermine, phenylethylamine, putrescine, cadaverine, tyramine. The highest HA content was determined in the group of fish (57.25 nmol/g) and corresponds to the statutory limits of Commission Regulation (EC) no. 2073/2005 on microbiological criteria for foodstuffs. In general, products with a lower proportion of fish are lower in lysine and alanine, but higher in some other AAs. In fermented fish, the content of GABA and all BAs is also higher. During the individual stages of the process, the content of GABA, BA and AAs changes. This causes an increase in the average concentration of all analyzed AAs and some BAs (histamine, agmatine, putrescine). During cooking and after sterilization, the percentage of water in the fish decreases, which increases the proportion of protein in fat during these stages of the process. Consequently, cooking decreases the AAs content, but the content after cooking is generally higher than in fresh fish. During thawing and cooking, different proportions of BAs and AAs are released into the water. The concentrations of GABA, BAa and AAa in individual fresh fish are highly correlated with each other. Individual fish show a high variability in size, weight, basic chemical composition and in content of certain compounds – AAs, BAs and others. Better findings would require examination of a larger number of samples and more parallels.
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