3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
P21 bIOGENIC AMINES IN ChEESES AND huMAN
hEALTh
ZUZAnA DIČáKOVá and eVA DUDRIKOVá
University of Veterinary Medicine, Komenského 73, 041 81
Košice, Slovak Republic,
dicakova@uvm.sk
Introduction
Food safety is an increasingly important public health
issue. Governments all over the world are intensifying their
efforts to improve food safety. These efforts are in response to
an increasing number of food safety problems and rising consumer
concerns 1 . Like of other processed foods, also cheeses
result from a manufacturing process involving the selection
of raw material (e.g. milk, lactic acid bacteria, rennet), preparatory
treatments such as milk pasteurization, renneting, drainage,
salting, the ripening operation proper, preservation (if
needed), packaging and storage. Last but not least, treatment
of the food by the consumer influences its condition. Thus, an
integral approach should be taken when assign the implications
of individual risk factors for the safety of the consumer 2 .
Cheeses are among those high-protein-containing foodstuffs
in which enzymatic and microbial activities cause the
formation of biogenic amines from amino acid decarboxylation
(Innocente et al., 2007). Codex Alimentarius of the Slovak
Republic stated the maximum limit only for the tyramine
in hard cheeses, in which the concentration of tyramine must
not exceed value of 200 mg kg –1 .
The aim of this study was to determine cadaverine
(CAD), histamine (HIS), tyramine (TYR) and putrescine
(PUT) in some commercial cheeses commonly consumed
in Slovakia using ion-exchange chromatography. Chemical
analyses were carried out in parallel with determination of
sensory assessment of cheeses and their microbiological quality
with the respect of Enterobacteriaceae.
Experimental
In total 31 samples of five cheese typologies were taken
from supermarkets and retail shops: 5 high cooked cheeses,
like Emmental, 8 low cooked cheeses, like Edam, 9 mozzarella
like cheeses, 5 mould cheeses, and 4 sour natural
ripened cheeses containing yeasts and Brevibacterium linens.
All products were sampled during the correct their shelf life.
Samples were stored at 4 ° C until to analysis.
B i o g e n i c A m i n e s A n a l y s i s
The five biogenic amines (BA) studied were: cadaverine
(CAD), histamine (HIS), tyramine (TYR) and putrescine
(PUT). Ion exchange chromatography with amino acid analyzer
(AAA 339 – T Microtechna, Czech Republic) was used
for both qualitative and quantitative studies of biogenic amines
in cheeses 3 .
Each sample (100–200 g) was homogenised and mixed
thoroughly with a Moulinex blender on a day of collection or
purchase. A 10 g sample was extracted with 5% trichloracetic
s617
acid, centrifuged and filtrated through a membrane filter with
a pore size of 0.45 μm. All the samples were prepared and
analysed in duplicates.
M i c r o b i o l o g i c a l A n a l y s i s
All cheese samples were subjected to microbiological
routine analysis: Enterobacteriaceae, E. coli, Staphylococcus
aureus, yeasts and moulds. The cultured selective agar plates
(blood agar, VRBG Agar, Endo Agar, Baird-Parker Agar;
Oxoid, UK) were used. Petri dishes were inoculated with
0.1 ml of diluting sample and cultivated in aerobic conditions
24–48 h at 37 °C and 25 °C for five days, respectively. Pure
cultures were identified at species by routine microscopical,
cultivation and biochemical methods. Micromycetes were
identified macroscopically and microscopically, using the
method according to St-Germain and Summerbell 4 .
S e n s o r y E v a l u a t i o n
Six volunteers (all women) were evaluated attributes
related to the flavour and mount feel of all type of cheeses
used in the experiment. The descriptor chosen were: colour,
consistency, mouth couting, cheese flavour intensity, sourness,
bitterness, off-flavour, and overall acceptability.
Results
The mean value of biogenic amine sum (CAD + H
IS + TYR + PUT) concentration in mg kg –1 varied from
9.82 in cheese with moulds to 1,092.33 in sour natural
ripened cheeses. In both groups of hard cheese the mean
value of the sum biogenic amine concentration was very
similar (175.05 mg kg –1 in high cooked cheeses versus
198.32 mg kg –1 in low cooked cheeses). The prevailing amine
in all cheeses included into the experiment was tyramine, following
by histamine, although HIS was not detected in any
case of mozzarella-like cheeses evaluated.
Enterobacteriaceae count ranged from
1.12 × 10 3 CFU g –1 (high cooked cheese samples) to
21 × 10 3 CFU g –1 in cheese with mould. Totally, Enterobacteriaceae
were isolated in 19 (61.29 %) of 31 evaluated cheese
samples in this study.
According to the sensory assessment, 87.01 % of evaluated
cheese had characteristic organoleptic properties
depending on the kind of cheese. In four of 31 evaluated cheeses,
the cheese samples did not show excellent sensory qua-
Table I
Concentration of BA in low cooked cheeses and Enterobacteriaceae
count (Ent) (CFU × 10 3 g –1 )
Col. stats HIS TYR PUT CAD Sum Ent
[mg kg –1 ]
Mean 8.5 134.8 13.2 18.0 173.5 8.2
sd 10.6 128.6 16.5 25.0 138.9 12.1
Minimum 1.0 1.30 0.0 0.0 8.00 0.0
Maximum 33.2 305.1 39.9 64.8 324.0 32.5
Median 4.5 111.7 3.9 8.2 173.5 1.0