3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
P52 MONITORING OF ACRyLAMIDE IN FOODS
IN ThE CZECh REPubLIC
JAnA KOLářOVá, IREnA řEHůřKOVá and JIří
RUPRICH
National Institute of Public Health – Centre for Hygiene of
Food Chains, Palackeho 3a, 612 42 Brno, Czech Republic,
kolarova@chpr.szu.cz
Introduction
Acrylamide is a substance that is produced, first of all
(but not exclusively), in starch foods as a result of high temperature
(> 120 °C) used during culinary processes, particularly
during baking, grilling, frying or microwaving. Acrylamide
can cause cancer in animals and experts assume that
acrylamide can probably cause cancer also in humans 1,2 .
The main mechanism of acrylamide formation in food
is expected via a reaction between the amino acid asparagine
and reducing sugars, e.g. glucose, under high temperature 1,3 .
Methodology
Since 2004, content of acrylamide has been monitored
within the framework of “The Project on Dietary Exposure of
the Czech Population to Selected Chemical Substances”carried
out by the Centre for the Hygiene of Food Chains in Brno
with the objective to describe the dietary exposure of the
Czech population to chemical substances.
Sample collection is designed to cover current diet composition
and also various regions in the country. Important
feature of the monitoring project is a fact that samples are
culinary treated so that they could be analysed in the same
stage as they are consumed 4 .
The determination of acrylamide is conducted in starchrich
foods but also othercomm. commodities, where acrylamide
was previously detected 5 (for example olives, coffee
and so on) within the range of so-called “Food basket for the
Czech population”. Individual commodities were purchased
four times per year.at a retail market of twelve towns in
the CR 6 .
The acrylamide is isolated from a matrix by the extraction
to 100 ml demineralised warm water (60 °C). After 20 min.
mixing the sample is centrifuged at 11,000 rpm for 10 min.
7 ml of supernatant is then transferred into a stoppered flask
containing 2 g anhydrous potassium bromide. Derivatization
(conversion of acrylamide into 2,3-dibromopropionamide)
is a next step. 2.5 ml saturated solution bromine (100 ml
H 2 O + 3 ml bromine) were added into stoppered flask with
sample. A product of bromination (over night reaction) was
extracted with 2.5 ml ethylacetate and converted into stable
2-bromopropenamide by dehydrobromination with triethylamine.
The ethylacetate extract is filtered and analysed by gas
chromatography (HP 5890) coupled with mass spectrometry
(HP 5972) employing 13 C 3 acrylamide as the internal standard.
The m/z 149 and 151 were used in the method of quantification
(SIM) of 2-bromopropenamide and the m/z 152 and
s687
154 for labelled 2-bromopropenamide. The ions separated by
two mass units are due to the contribution of the two isotopes
of bromine. The ratio of 79Br to 81Br is 1 : 1, which enables
us to choose between the above m/z in the process of quantification.
The m/z value, which isn‘t influenced by interference,
is chosen.
The method was validated and accredited according to
CSn En ISO/IEC 17025 (Czech Accreditation Institute). The
quality control was implemented by participating in proficiency
testing organised by Food Analysis Performance Assessment
Scheme (FAPAS).
In addition, FAPAS samples of known acrylamide content
were used as reference materials for internal testing.
Results and Discussion
In total 803 various samples were analysed during
2005–2007. The highest content of acrylamide was found in
potato crisps (range 268–3,817 µg kg –1 ), french-fries (range
< 15–705 µg kg –1 ), honey gingerbread (73–429 µg kg –1 ),
cocoa powder (56–567 µg kg –1 ). Relatively high acrylamide
levels were detected in spices (147–1,076 µg kg –1 ).
Table I
Acrylamide content in food samples (2005–2007)
Commodity n µg kg –1
Potato crisps 36 267.88–3817.48
French fries 33 < 15–704.65
Ground paprika 12 147.39–1075.98
Pepper 12 182.06–456.48
Biscuits 36 50.19–1337.24
Savoury biscuits 24 68.70–708.38
Gingerbread 24 73.36–429.18
Cocoa powder 24 55.63–566.91
Wafers 36 22.00–420.94
Plain chocolate 12 61.11–246.86
Cornflakes 24 < 15–299.48
Cake 24 15.59–190.24
Muesli 24 < 15–195.36
Flaky pastry 12 22.54–146.93
Wheat-rye bread 24 19.84–83.58
Rye bread 36 < 15–92.67
Cream cake 26 < 15–97.51
Wholemeal bread 36 < 15–87.09
Wholemeal rolls 36 < 15–98.19
Pizza 12 < 15–66.29
Chocolate sweets 36 < 15–83.01
Chocolate bars 36 < 15–123.22
Wheat rolls 24 17.78–70.26
French loaf 24 16.17–53.67
Milk chocolate 12 28.19–63.49
Coffee (infusion) 12 4.42–21.81
Peanuts 12 < 15–48.97
Sponge biscuits 24 < 15–34.79
Cocoa instant drink 12 < 15–20.84