Contents of some biologically active amines in a Czech blue-vein cheese

Biogenic amines (histamine, tyramine, tryptamine, phenylethylamine, cadaverine) including biologically active polyamines (putrescine, spermidine and spermine) were determined by HPLC method after 7, 21, 35, and 49 days of ripening in the core (C) and edge (E) samples of a blue-veined cheese, popular in the Czech Republic under the trade mark Niva, produced in the three consecutive months (October, November, December) from pasteurised cow milk using Penicillium roqueforti spores; two vats were produced in each month. The cheese vat, including the production period, accounted for (P < 0.05) one third and two thirds of the explained variability of the sum of biogenic amines and the sum of polyamines, respectively. The ripening time was significant (P < 0.05) from this viewpoint only in the case of the sum of biogenic amines (nearly half of the explained variability). Putrescine and spermidine contents in cheese did not change (P > 0.05), spermine content even decreased (P < 0.05) with increasing time of ripening. Tyramine content (Y, mg/kg) in the core samples increased linearly with increasing time of ripening (X, days), Y = 6.3 + 11.69X, R2 = 0.26, P < 0.001, contrary to the edge part where tyramine content did not change (P > 0.05). At the end of ripening (49 days), tyramine was quantitatively the most abundant amine (the mean and median 380 mg/kg and 289 mg/kg, respectively), its content in different cheeses (vats) varying from 10 mg/kg to 875 mg/kg. Cadaverine concentration varied between 3 mg/kg and 491 mg/kg (the mean 114, median 56 mg/kg). The levels of other biogenic amines and polyamines (with the exception of putrescine in the edge part of one of the December vats: 117 mg/kg) were very low even at the end of ripening. Tyramine contents at the end of ripening in the core-samples were higher (P < 0.01) in comparison with those in the edge-samples, contrary to histamine, cadaverine, putrescine, and spermine contents.