Formation of biogenic amines and vitamin K contents in the Norwegian autochthonous cheese Gamalost during ripening

International audienceGamalost, a Norwegian mould (Mucor mucedo) ripened autochthonous cheese, is a potential functional food due to a high content of peptides that might reduce hypertension, however it has a high content of free amino acids which may be precursors for biogenic amines. This study aimed to investigate if Gamalost might have further health benefits or risks by determination of the formation of vitamin K and biogenic amines. The development of biogenic amines and vitamin K was analysed during ripening. Putrescine was the only biogenic amine detected by liquid chromatography in ripened Gamalost, in the range from 11 to 25 mg.kg−1. The presence of very low concentrations of biogenic amines may suggest that Gamalost is devoid of hazards posed on health. The menaquinones (vitamin K2) detected in Gamalost by high-performance liquid chromatography were MK-4 to MK-10 and among them, MK-9 was found in the significantly highest concentration (46 μg.100 g−1). The menaquinone content of Gamalost was attributed to the activities of the starter lactic acid bacteria used for fermentation during manufacture. Gamalost contained a significantly higher menaquinone content than Norvegia, a Norwegian cheese

The effects of different processing conditions on biogenic amine formation and some qualitative properties in pastırma

PastA +/- rma, a Turkish dry-cured meat product, was cured at two different temperatures (4 or 10 A degrees C) with two different curing agents (150 mg/kg NaNO2 or 300 mg/kg KNO3). The aim of this research was to determine the effects of these factors on biogenic amine content and other qualitative properties (pH, a(w), color, residual nitrite, TBARS, NPN-M, microbiological properties). Residual nitrite was below 10 mg/kg in all samples. Both the curing agent and temperature were found to have a very significant effect on the TBARS value, and the curing agent had a significant effect on the NPN-M content. Curing at 10 A degrees C increased the L* value; the use of nitrate increased the a* value. The use of nitrite had a negative effect on the growth of lactic acid bacteria. Micrococcus/Staphylococcus showed good growth in the presence of nitrate. In all samples, Enterobacteriaceae counts were below detectable levels. Neither temperature nor curing agent had significant effects on the amounts of tryptamine, cadaverine, histamine, tyramine, or spermine. There were very significant effects of temperature on the amount of putrescine and of the curing agent on the amount of spermidine

Sensitivity to Enterocins of Biogenic Amine-Producing Faecal Enterococci from Ostriches and Pheasants

Enterococci are widespread bacteria forming the third largest genus among lactic acid bacteria. Some possess probiotic properties or they can produce beneficial proteinaceous antimicrobial substances called enterocins. On the other hand, some enterococci produce biogenic amines (BAs), so this study is focused on the sensitivity to enterocins of biogenic amine-producing faecal enterococci from ostriches and pheasants. Altogether, 60 enterococci isolated from faeces of ostriches and pheasants were tested for production of BAs. This target of the identified enterococci involved 46 strains selected from 140 ostriches and 17 from 60 pheasants involving the species Enterococcus hirae, E. faecium, E. faecalis, and E. mundtii. Although BAs histamine, cadaverine, putrescine, and tryptamine were not detected in the enterococci tested, in general high BA production by the tested enterococci was noted. The species E. hirae formed the majority of the enterococcal strains from ostrichs faeces (34 strains). High production of tyramine (TYM) was measured with an average amount of 958.16 ± 28.18 mg/ml. Among the enterococci from pheasants, the highest was production of TYM compared to phenylethylamine, spermidine, and spermine. Enterococci featured high BA production; however, they were sensitive to seven enterocins with inhibition activity ranging from 100 up to 25,600 AU/ml. © 2017, Springer Science+Business Media New York.2/0004/14, VEGA, Vedecká Grantová Agentúra MŠVVaŠ SR a SAV; 2/0006/2017, VEGA, Vedecká Grantová Agentúra MŠVVaŠ SR a SAVSlovak Scientific Agency VEGA [2/0004/14, 2/0006/17