The sequential determination of nitrite, N-nitroso compounds and nitrate and its application

Area of Science:

• Analytical Chemistry
• Food Science
• Toxicology

Background:

• Nitrite and N-nitroso compounds are prevalent in food and biological systems.
• Accurate detection methods are crucial for food safety and health risk assessment.
• Existing methods may lack sensitivity or specificity for certain compounds.

Purpose of the Study:

• To develop a selective method for determining nitrite, nitrate, and N-nitroso compounds in food matrices.
• To quantify nitric oxide released from these compounds under specific chemical conditions.
• To assess the presence of these compounds in animal diets using the developed method.

Main Methods:

• Direct quantification of nitric oxide released from food samples.
• Sequential addition of acetic acid, hydrogen bromide, and titanous chloride under nitrogen.
• Utilizing refluxing solvent system for compound decomposition.
• Gas chromatography with a Thermal Energy Analyzer detector for confirmation.

Main Results:

• The method selectively determines nitrite, nitrate, and N-nitroso compounds.
• Low levels of nitrite, below detection limits of conventional methods, were found in animal diets.
• Non-volatile, non-extractable N-nitroso compounds were detected in both treated and untreated diets.
• Morpholine was confirmed to convert into its N-nitroso derivative in an untreated diet.

Conclusions:

• The developed method offers a sensitive and selective approach for analyzing nitrite and N-nitroso compounds.
• It reveals the presence of concerning levels of these compounds in food matrices.
• The findings highlight potential risks associated with seemingly untreated food products.