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Detekce biogenních aminů u konzervovaných výrobků z ryb
Zátopková, Tereza
The aim of my work was to conduct a literature search on biogenic amines and to detect the content of biogenic amines in canned fish products in the laboratory part. Four fish spe-cies were sampled for the determination: mackerel (Scomber scombrus), bluefin tuna (Thun-nus thynnus), sardine (Sardina pilchardus) and cod (Gadus morhua). Two samples were used for the determination of sardines, which differed in the brine in which they were preserved. The detection of biogenic amines was carried out by ion-exchange liquid chromatography with VIS detection. The following specific biogenic amines were determined: histamine, tyramine, putrescine, cadaverine, spermine and spermidine. The highest concentration of biogenic was determined in the sample of liver, in this sample the overall highest contents of histamine, putrescine, cadaverine and spermine were found.
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Vliv receptury a délky zrání na obsah biogenních aminů ve zrajících sýrech
Trusinová, Adéla
The diploma thesis is focused on the content of biogenic amines (cadaverine, histamine, 2-phenylethylamine, tyramine and tryptamine) depending on the ripening time in 3 varieties of maturing cheeses (control sample, sample with laccase in the cheese dough, sample with laccase on the surface of the cheese). Furthermore, the work focuses on the effect of adding laccase to the dough and on the surface of the cheeses. The theoretical part is focused on the importance and occurrence of biogenic amines in food, including possible toxic effects on the organism. The practical part monitored the effect of ripening time on the content of biogenic amines in 3 variants of the same type of cheese in the ripening process. Biogenic amines were determined after derivatization with dansyl chloride by HPLC. The most quantitatively represented biogenic amine was cadaverine, which reached the highest concentration values after 14 days of ripening in cheese with laccase on the surface. The value of the concentration was 336 μg/100 g. The amount of laccase on the surface showed an opposite trend (p ˂0.05) when evaluating the storage time on the content of the concentration of biogenic amines, an opposite trend against cheeses with laccase in the dough. The concentration of the sum of biogenic amines in all cheese samples with laccase in the dough first decreased, then increased according to the equation y = 556.03–165.51x + 22.593x2 (R² = 0.4904; p = 0.14). The concentration of the sum of biogenic amines in cheeses with laccase on the surface, depending on the ripening time, first increased and then decreased according to the equation y = 150.42 + 631.63x - 97.921x2 (R² = 0.1999; p = 0.57). Most of the values measured in this work do not correspond to the normal content of individual biogenic amines in the literature, this fact may be caused by an inappropriate selection of the type of cheese for the determination of biogenic amines, an incorrect technological procedure during production or the fact that the filtration of the supernatants was very difficult and lengthy and with large losses. The influence of laccases on the formation of biogenic amines could not be unequivocally demonstrated due to the great variability of the data and few reference values with which the measured values can be compared. Laccases in food are a relatively new issue that is not sufficiently supported by literature sources and requires further investigation.
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Stanovení biogenních aminů v sortimentu zrajících sýrů
Bubelová, Kristýna
The diploma thesis focuses on the content of biogenic amines (BA: tyramine, histamine, kadaverine, tryptamine, phenylethylamine) and polyamines (PA: putrescine, spermine, spermidine) in eidam, emmental and parmesan cheese. The theoretical part describes the origin, occurrence and importance of BA and PA, and the various factors influencing their occurrence. In the practical part, the influence of the type of cheese, temperature and storage time on the content of individual amines was monitored. The most significant amines in all types of tested cheeses were tyramine (eidam 173,3 mg/kg > emmental 4,4 mg/kg = parmesan 10,9 mg/kg) and putrescine (eidam 188,4 mg/kg > emmental 77,5 mg/kg = parmesan 36,4 mg/kg). When compared to all types of monitored cheeses stored for 3 weeks, there was a tendency (p > 0,05) to increase the BA content and decrease the PA content in the cheeses stored at 20 °C compared to the cheese stored at 5 °C (tyramine 128,1 mg/kg vs. 62,9 mg/kg, putrescine 61 mg/kg vs. 100,8 mg/kg). During storage (X, weeks), the tyramine content (Y; mg/kg) in eidam and emmental was increased by the following equation: y = 82,2 + 28,9x (R2 = 0,34, p = 0,005) and y = -10,7 + 5,17x (R2 = 0,23, p = 0,025). The corresponding regression for the content of PUT (on the other hand, the reduction of content) in emmental and parmesan was as follows: y = 230,1 – 63,63x + 4.249x2 (R2 = 0,92, p < 0,001) and y = 48,6 – 6,07x2 (R2 = 0,24, p = 0,024).
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Current knowledge about histamine intolerance and benefits of elimination diet
Krlínová, Michaela ; Tomešová, Jitka (advisor) ; Suchánek, Pavel (referee)
With increasing interest about one's own health and in relation to the development of research, a new nosological unit - histamine intolerance - appeared about ten years ago. Completely healthy people can experience its symptoms and histamines can be found in common food. Therefore, among the professional public there are disunited opinions on its importance and contribution of a precisely specified elimination diet. Bachelor thesis research through recent literature assesses the current knowledge about seriousness of this new nosological unit, its occurrence and impact on human health as well as the occurrence of histamines in common food. Thesis discusses already known conclusions and the possibilities of abide by the appropriate elimination diet, including its merit to alleviating symptoms and improving the health of individuals afflicted with histamine intolerance.
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Biogenní aminy ve fermentovaných mléčných výrobcích
Bubelová, Kristýna
This bachelor thesis is focused on biogenic amines in fermented dairy products, particularly in cheeses. Biogenic amines are low molecular weight nitrogenous base formed mainly by decarboxylation of free amino acids by treatment with bacterial de-carboxylation enzymes. The most important bacteria forming biogenic amines in cheese are part of contaminating microflora (e.g. Enterococcus) and starter cultures (e.g. Lactobacillus). The cheeses are most prone to histamine, tyramine, cadaverine, putrescine. Furthermore, the work described effects, factors affecting the incidence and methods of determination.
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The formation of biogenic amines in flesh of selected fish species
MATĚJKOVÁ, Kateřina
The thesis deals with the use and effectiveness of some less common methods of conservation of fish meat. The formation of biogenic amines in meat is observed in connection with the non-traditional preservative methods. Amines can serve as indicators of protein degradation. The quality of fish was considered in connection with the increasing content of selected biogenic amines (putrescine, cadaverine, spermidine, spermine, 2-fenylathylamine, histamine, tyramine and tryptamine). Ultra performance liquid chromatography (UPLC) was used as the method for determination of biogenic amines. Amines were derivatized by dansylchloride before their UPLC separation. The fish flesh was vacuum-packed. Samples were stored for several weeks in a thermostat at the selected storage temperature after the application of selected preservative technique. Beta-irradiation and high hydrostatic pressure were used for the preservation of fish flesh. Control samples were not exposed to the â-irradiation and high pressure. The organoleptic properties were studied for all samples (smell/odor, insight and shape). Beta-irradiation was applied to fish meat of common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss). Both these species of freshwater fish are economically significant. Carp and trout are the species being mostly consumed in the Czech Republic. Fish meat is considered to be provided the flesh is fresh. A testing series of samples was created with common carp to determine the appropriate dose of â-irradiation. The maximum permissible dose of irradiation for fish meat is 3 kGy. Fish samples were exposed this dose in the first experiment. The dose of irradiation was reduced in following experiments based on the experience from the initial experiment. The doses of 0.25, 0.5, 0.75, 1.0 and 2.0 kGy were applied to rainbow trout. The value of 0.75 kGy of â-irradiation or higher (1.0, 2.0 and 3.0 kGy) prolonged the shelf life of fish meat, which was stored for three months (98 days). Prolonging of the shelf life of fish meat to approximately 98 days at 3.5 °C is redundant from technical point of view. For that reason lower doses 0.25, 0.5 and 0.75 kGy were tested in more detail in the repeated experiment with carp meat. Lower doses of â-irradiation are considered to be more acceptable and-at the same time-sufficiently effective for delaying the beginning of degradation processes. 6 High hydrostatic pressure was applied to meat of common carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss) and pike (Exos lucius). Pike is another very popular kind of freshwater fish. Pike flesh is very tasty, but in spite of this, pike is not so much popular among consumers compared to carp and trout. The cause is its high price. Samples of pike were stored at standard temperature 3.5 °C and also at higher temperature 12 °C (unlike experiments with â-irradiation). Lower temperature of storage (3.5 °C) followed the conditions of storing of fish meat in industrial refrigeration facilities and households. The high pressure might not be sufficient for preservation at higher storage temperatures. This assumption was based on available information. Samples were treated by high pressure and stored at both 3.5 °C and 12 °C to verify this assumption. Higher temperature simulated either failure of refrigeration equipment or unsuitable store temperature of meat. In all species selected freshwater fish two levels of high pressure were applied ? 300 and 500 MPa. Both levels had significantly reduced the formation of biogenic amines, especially in samples stored at 3.5 °C. At this temperature, the effect of 300 and 500 MPa delayed start of degradation processes in fish meat by 3?4 weeks. At 12 °C and 500 MPa, high pressure extended the sustainability of meat by no more than one week. 500 MPa is effective treatment at the lower temperature of 3.5 °C. High pressure is not reliable preservative techniques at higher temperature.
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