2009_Book_FoodChemistry

9.7 Harmful Substances from Thermal Processes 491
Fig. 9.4. Formation of furan on heating food (according to Yaylayan, 2006)
into Category III A2 of carcinogenic working
substances. According to EU guidelines for
drinking water, the concentration of acrylamide
in water should not exceed 0.1µg/l.
The occurrence of relatively high concentrations
of acrylamide in tobacco smoke has been known
for a long time, but in 2002 this compound was
described for the first time also as a constituent
in various thermally treated foods. In particular,
processed potato products such as chips, but
also fine breads and cakes contain relatively high
concentrations (Table 9.11). Today, mainly stable
isotope assays in combination with GC–MS
or LC–MS with the use of deuterium- or carbon-
13-labelled acrylamide are used for the quantitative
determination. The large range of variations
in the concentrations measured in food indicates
that the raw material and the process conditions
exert a significant influence on the formation
of acrylamide. Thus, it could be shown, e. g.,
that the formation of acrylamide in potato products
clearly fluctuates depending on the variety of
potato (Fig. 9.5) and the concentrations of acryl-
Table 9.11. Maximum concentrations and variation
ranges of acrylamide in selected foods
Food
Concentration (µg/kg)
Gingerbread 7800 (80–7800)
Potato chips 3700 (100–3700)
Crispbread 2800 (25–2800)
Roasted nuts 2000 (10–2000)
Ground coffee 500
Roasted meat 50
Bread 40
Fig. 9.5. Formation of acrylamide during the frying of
potato strips from different varieties of potatoes (according
to Amrein et al., 2003)