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Absolute quantification for benzoic acid in processed foods using quantitative proton nuclear magnetic resonance
Takashi Ohtsuki1, Kyoko Sato, Naoki Sugimoto
1National Institute of Health Sciences, 1-18-1 Kamiyoga, Tokyo 158-8501, Japan. ohtsuki@nihs.go.jp
Talanta
|September 13, 2012
Summary
A new method accurately quantifies benzoic acid (BA) in processed foods using NMR spectroscopy. This rapid, simple technique offers reliable results for food safety monitoring.
Area of Science:
- Food Science
- Analytical Chemistry
- Spectroscopy
Background:
- Benzoic acid (BA) is a common food preservative.
- Accurate quantification of BA in processed foods is crucial for regulatory compliance and consumer safety.
- Existing methods for BA quantification can be time-consuming and complex.
Purpose of the Study:
- To develop and validate a novel method for the absolute quantification of benzoic acid in processed foods.
- To establish a rapid, simple, and accurate analytical technique for BA determination.
- To provide a method with International System of Units (SI) traceability without requiring authentic analyte standards.
Main Methods:
- Solvent extraction of benzoic acid from processed food matrices.
- Quantitative proton nuclear magnetic resonance (qH-NMR) spectroscopy using 2-dimethyl-2-silapentane-5-sulfonate-d(6) sodium salt (DSS-d(6)) as an internal reference.
- Validation of the method through recovery studies and comparison with conventional techniques.
Main Results:
- The developed method demonstrated high recovery rates (>80%) across various processed foods.
- The limit of quantification was established at 0.063 g kg(-1), suitable for monitoring purposes.
- The accuracy of the qH-NMR method was found to be equivalent to traditional methods like steam distillation and HPLC.
- The method proved to be rapid and simple to perform.
Conclusions:
- The developed solvent extraction and qH-NMR spectroscopy method is a practical and reliable tool for determining benzoic acid levels in processed foods.
- This method offers SI traceability, enhancing its utility in regulatory and quality control settings.
- The technique provides a faster and simpler alternative to existing analytical procedures for benzoic acid quantification.
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