2009_Book_FoodChemistry

494 9 Food Contamination
Nitrosamine formation is also possible from primary
amines:
from diamines:
(9.8)
Table 9.15. Nitrosamines in food
Food product
Compound a Content µg/kg
Frankfurter
(hot dog) NDMA 0–84
Fish (raw) NDMA 0–4
Fish, smoked and
pickled with nitrites
or nitrates NDMA 4–26
Fish, fried NDMA 1–9
Cheese (Danish, Blue,
Gouda, Tilsiter,
goatmilk cheese) NDMA 1–4
Salami NDMA 10–80
Bacon (hog’s hind leg)
smoked meat NDMA 1–60
Pepper-coated ham,
raw and roasted NPIP 4–67
NPYR 1–78
a NDMA: N-Nitrosodimethylamine, NPIP: N-nitrosopiperidine,
NPYR: N-nitrosopyrrolidine.
and from tertiary amines:
(9.9)
Nitrosamines are detected in variable amounts
in many foods (Table 9.15). The most common
compound is dimethylnitrosamine, which is also
a most powerful carcinogen. Some activity has
been ascribed to nitrosopiperidine and nitrosopyrrolidine.
In meat products cured and treated with
pickling salt, 30% of the samples contained nitrosodimethylamine
(NDMA; 0.5–15 µg/kg) and
13% nitrosopyrrolidine (NPYR; >0.5µg/kg).
About 25% of the cheese samples analyzed were
contaminated (0.5–4.9µg/kg).
Nitrosopyrrolidine is formed from the amino acid
proline by nitrosation followed by decarboxylation
at elevated temperatures, such as in roasting
or frying:
(9.10)
(9.11)
(9.12)