Effects of storage temperature on biogenic amine concentrations in meat of uneviscerated pheasants ( Phasianus colchicus )

The aim of this study was to determine the hygienic quality of the pheasants reared for highquality meat production by the biogenic amine concentrations in their meat. The content of biogenic amines was measured in the meat of sixty male pheasants killed by pithing and stored uneviscerated for 21 days under different storage temperatures (0 °C, 7 °C and 15 °C). The samples of breast and thigh muscles of pheasant were tested at weekly intervals. Biogenic amines were analysed by reverse phase liquid chromatography and detected by tandem mass spectrometry. Concentrations of biogenic amines (except spermin and spermidin) in thigh muscle were higher than in breast muscle. Highly significant difference (P < 0.01) was found in tyramine (5.80 mg/ kg and 1.38 mg/kg for thigh and breast muscle, respectively), cadaverine (40.80 mg/kg and 14.43 mg/kg for thigh and breast muscle, respectively), putrescine (13.42 mg/kg and 3.16 mg/kg for thigh and breast muscle, respectively) and histamine (5.51 mg/kg and 1.70 mg/kg for thigh and breast muscle, respectively) concentrations after 21 days of storage at 15 °C. This study provides information on the dynamics of biogenic amine formation in pheasant meat during 21 days of storage at different temperatures. Based on our results, we can recommend storing pithed uneviscerated pheasants at 0–7°C for up to 21 days, or at 15 °C for up to 7 days. Concentrations of biogenic amines gained in our study can be helpful in evaluating freshness and hygienic quality of the pheasant game meat. Putrescine, cadaverine, tyramine, game meat, hygienic quality, pithed pheasant Biogenic amines are low-molecular weight nitrogen compounds formed mainly by decarboxylation of amino acids or amination and transamination of aldehydes and ketones (Santos 1996). Biogenic amines in food are formed as a result of the growth of decarboxylase-positive microorganisms under conditions propitious for that enzyme activity. Production of biogenic amines in foods is associated with the presence of microorganisms and their activity in food (Halasz et al. 1994). The monitoring of biogenic amine concentrations is very important because, from the human health point of view, their presence in food at elevated concentrations has been involved in various cases of foodborne diseases and cases of human poisoning (Shalaby 1996), and has been associated with negative effects on human heath (Balamatsia et al. 2006; Gallas et al. 2010; Naila et al. 2010; Standarova et al. 2012) and various other toxicological effects (HernandezJover et al. 1997). Biogenic amine concentrations in meat and meat products have been studied by many authors. It has been established that high biogenic amine concentrations in meat and meat products are generated as a result of microbial contamination and improper storage conditions (Santos 1996). In terms of human health, the most important biogenic amines are putrescine, cadaverine, histamine, tyramine, spermine, spermidine and betaphenylethylamine (Sahalaby 1996). While spermine and spermidine are always present in meat and meat products, concentrations of the other biogenic amines vary (HernandezJover et al. 1996, 1997). Biogenic amines serve as indicators of poor quality of meat ACTA VET. BRNO 2013, 82: 061–065; doi:10.2754/avb201382010061 Address for correspondence: MVDr. Zdeňka Hutařova Department of Veterinary Public Health and Toxicology Faculty of Veterinary Hygiene and Technology University of Veterinary and Pharmaceutical Science Brno Palackeho tř. 1/3, 612 42 Brno, Czech Republic Phone: +420 54156 2789 E-mail: hutarovaz@vfu.cz http://actavet.vfu.cz/ and meat products (Durlu-Ozkaya et al. 2001). Putrescine, cadaverine, histamine and tyramine are considered freshness markers and can be used as indicators of microbial spoilage (Boka et al. 2012). Biogenic amines in poultry have been studied by Silva and Gloria (2002), Balamatsia et al. (2006) and Tamim and Doerr (2003). In feathered game, biogenic amines may be highly significant as indicators of hygienic quality. This is because of the customary handling of game birds, which are hung in feathers for a period of several days to improve sensory quality of their meat. In view of game bird microbial contamination and temperature variables during hanging, we might assume a deterioration of hygienic quality of the game and an associated marked increase in biogenic amine content in the meat of game birds. Paulsen et al. (2008) looked into the issue of biogenic amines in uneviscerated pheasants. Raising pheasants for slaughter and the subsequent meat production has recently acquired great importance (Hofbauer et al. 2010). Consequently, the question of biogenic amine concentrations in the meat of slaughtered or pithed pheasants has also become very important. The issue of biogenic amines in the meat of pithed pheasants has been dealt with by Standarova et al. (2012). The aim of our experiment was to study how long uneviscerated pheasant carcasses may be stored at different temperatures (0 °C, 7 °C or 15 °C) by the content of biogenic amines in the meat of common pheasant slaughtered (pithed) for meat production. Materials and Methods In our experiment we used 60 male common pheasants of a mean weight of 1 250 g ± 183 g. The pheasants were killed by pithing which means interrupting their spinal cord and destroying the brain. Pheasant carcasses were not eviscerated (the body cavity was not opened), which is a standard procedure for handling feathered game. Then, carcasses were divided into three groups of 20 birds each and placed into three different coolers each set at a different temperature (0 °C, 7 °C and 15 °C). We chose the storage temperature of 0 °C as a temperature at which no major changes in meat are expected due to low microbial activity at this temperature and hence no major changes in biogenic amine concentrations. The temperature of 7 °C was chosen in order to obtain data on changes in biogenic amine concentrations in meat at a temperature when some changes due to microbial contamination can already occur. The temperature of 15 °C was chosen as a temperature at which pheasant may be stored when hung in the open air, or in the case of e.g. some cooling system failure when pheasants are stored in coolers, and at which the development of microbial activity in pheasant meat is assumed. The storage period was 21 days. During this period at regular weekly intervals on days 1, 7, 14 and 21 after, they were killed, samples of 5 pheasant carcasses from each group stored at a specific temperature were used for examination. To determine the concentration of biogenic amine (putrescine, cadaverine, histamine, spermidine, spermine, tyramine, phenylethylamine and tryptamine), breast and thigh muscles (m = 0.5g) were collected from each of the carcases. To ensure the representativeness of samples the collected breast and thigh muscles were pureed. From this homogenised material the amount of 0.5 g was consequently withdrawn for biogenic amines assessment. One-step extraction using mixtures of trichloracetic acid in water (5%) followed by clean-up step using 0.45 μm syringe filter was employed for sample preparation. Biogenic amines were subsequently separated by reverse phase liquid chromatography using C18 (2.1 mm × 50 mm, 1.9 μm; Thermo, San Jose, CA, USA) column and detected by tandem mass spectrometry using a heated electro spray-ionization in positive ion mode. Thermo Scientific UHPLC Accela 1250 system was connected to a Thermo Scientific TSQ Quantum Access MAX Triple Quadrupole Instrument (Thermo, San Jose, CA, USA). The results were processed by the Unistat 5.6 statistical software package and evaluated using the KruskalWallis test. Statistical difference was presented as P < 0.05 and P < 0.01.