N-nitroso compounds and mutagens in Chinese fermented (sour) corn pancakes

Area of Science:

• Gastroenterology
• Toxicology
• Food Science

Background:

• Stomach cancer incidence is exceptionally high in Linqu County, Shandong Province, China.
• Previous research linked daily consumption of sour (fermented) corn pancakes to a 30% increased risk of stomach cancer.
• Earlier studies reported mutagenic activity and volatile nitrosamines in sour pancakes.

Purpose of the Study:

• To investigate the mutagenic activity and N-nitroso compound (NOC) contamination in sour corn pancakes from Linqu County.
• To reassess the potential role of sour pancakes in the high stomach cancer rates observed in the region.

Main Methods:

• Samples of sour pancake batter and cooked pancakes were tested for mutagenic activity using the Ames test.
• N-nitroso compounds (NOC) were quantified using the Nitrolite-thermal energy analysis (TEA) method.
• Specific analysis for nitrosaminoacids and volatile nitrosamines was performed using gas chromatography-TEA.

Main Results:

• The Ames test yielded inconclusive results, with only one cooked pancake showing a positive mutagenic response and all batter samples testing negative.
• A weakly positive trend of mutagenicity was observed in some batter specimens with increasing extract concentration.
• Total N-nitroso compounds were weakly positive in only one out of 15 batter specimens; no nitrosaminoacids or volatile nitrosamines were detected.

Conclusions:

• Current evidence suggests it is unlikely that Chinese sour pancakes are significantly contaminated with N-nitroso compounds or other mutagens.
• The findings question the direct link between sour pancakes and the high stomach cancer rates in Linqu County.
• Further research is needed to identify the primary etiological factors contributing to the elevated stomach cancer incidence in this region.