Simultaneous determination of ethanol and methanol in non-alcoholic beverages by precolumn derivatization and liquid chromatography with fluorescence detection
Document Type : Original research
Authors
Department of Environmental Engineering & Mathematics, RheinMain University of Applied Sciences, Kurt-Schumacher-Ring 18, 65197 Wiesbaden, Germany
Abstract
The determination of ethanol content in non-alcoholic beverages is driven by health concerns and is often imposed by regulating agencies. On the other hand, methanol poisoning leads to high health risks. In addition, the application of the Halal concept in Islamic countries requires the availability of efficient analytical methods. This work reports the development of a simple and sensitive HPLC method for the simultaneous determination of ethanol and methanol in juices and beverages. The method is based on the formation of a stable derivative via the reaction of ethanol and methanol with 9-fluorenylmethyl chloroformate (Fmoc-Cl). The resulting derivatives are detected by a fluorescence detector. The method’s LODs and LOQs were 0.004 g/L and 0.01 g/L, for methanol, and 0.015 g/L and 0.05 g/L, for ethanol, respectively. The mean recovery ranged from 98–109% for both methanol (RSD = 3.7%), and ethanol (RSD = 4.1%). This approach of determination is sensitive and simple in that it requires only a 100 µL sample volume and the reaction product (derivative) can be directly injected without further extraction or pre-concentration. Analysis of a number of non-alcoholic drinks from the domestic market showed that the ethanol content ranged between 0.11 - 0.71 g/L.
Keywords
Main Subjects
Avila, L. M., dos Santos, A. P. F., de Mattos, D. I. M., de Souza, C. G., de Andrade, D. F., & d’Avila, L. A. (2018). Determination of ethanol in gasoline by high-performance liquid chromatography. Fuel, 212, 236–239.
Bunton, C. A., Mhala, M. M., & Moffatt, J. R. (1986). Micellar charge effects upon spontaneous nucleophilic additions and substitutions. In K. L. Mittal & P. Bothorel (Eds.), Surfactants in Solution: Volume 5 (pp. 625–635). Springer US. https://doi.org/10.1007/978-1-4615-7981-6_6
Burkhardtsmaier, P., Pavlovskaja, K., Maier, D., Schäfer, S., Salat, U., & Schmidt, M. S. (2021). Quantitative monitoring of the fermentation process of a barley malt mash by benchtop 1H NMR spectroscopy. Food Analytical Methods, 14(7), 1425–1431.
da Silva Nunes, W., de Oliveira, C. S., & Alcantara, G. B. (2016). Ethanol determination in frozen fruit pulps: An application of quantitative nuclear magnetic resonance. Magnetic Resonance in Chemistry: MRC, 54(4), 334–340.
David, S. (2018, May 8). More than 100 villagers return home after methanol poisoning—Khmer Times. https://www.khmertimeskh.com/487671/more-than-100-villagers-return-home-after-methanol-poisoning/
Febriani, Y., & Ihsan, E. A. (2020). Determination of ethanol in a distillate sample of arenga pinnata by uv-visible spectrophotometry. Journal of Physics: Conference Series, 1539(1), 012002.
Feng, Y., Su, G., Sun-Waterhouse, D., Cai, Y., Zhao, H., Cui, C., & Zhao, M. (2017). Optimization of headspace solid-phase micro-extraction (HS-SPME) for analyzing soy sauce aroma compounds via coupling with direct GC-Olfactometry (D-GC-O) and gas chromatography-mass spectrometry (GC-MS). Food Analytical Methods, 10(3), 713–726.
France-Presse, A. (2018, October 29). Death toll in Iran alcohol poisoning jumps to 84 victims. VOA. https://www.voanews.com/a/death-toll-in-iran-alcohol-poisoning-jumps-to-84/4633468.html
Garg, N., Sarkar, A., & Sundararaju, B. (2021). Recent developments on methanol as liquid organic hydrogen carrier in transfer hydrogenation reactions. Coordination Chemistry Reviews, 433, 213728.
Gaw, C. E., & Osterhoudt, K. C. (2019). Ethanol intoxication of young children. Pediatric Emergency Care, 35(10), 722.
Goldberger, B. A., Cone, E. J., & Kadehjian, L. (1996). Unsuspected ethanol ingestion through soft drinks and flavored beverages. Journal of Analytical Toxicology, 20(5), 332–333.
Gorgus, E., Hittinger, M., & Schrenk, D. (2016). Estimates of ethanol exposure in children from food not labeled as alcohol-containing. Journal of Analytical Toxicology, 40(7), 537–542.
Hämmerle, M., Hilgert, K., Horn, M. A., & Moos, R. (2011). Analysis of volatile alcohols in apple juices by an electrochemical biosensor measuring in the headspace above the liquid. Sensors and Actuators B: Chemical, 158(1), 313–318.
ICH Harmonised Tripartite Guideline. (2005). ICH Q2(R1) Validation of analytical procedures: text and methodology—ECA academy. International Conference on Harmonisation of Technical Requirements For Registration of Pharmaceuticals For Human Use, Geneva, Switzerland. https://www.gmp-compliance.org/guidelines/gmp-guideline/ich-q2r1-validation-of-analytical-procedures-text-and-methodology
Joint Research Centre (European Commission), Robouch, P., Stroka, J., Haedrich, J., Schaechtele, A., & Wenzl, T. (2016). Guidance document on the estimation of LOD and LOQ for measurements in the field of contaminants in feed and food. Publications Office of the European Union. https://data.europa.eu/doi/10.2787/8931
Konnert, L., Lamaty, F., Martinez, J., & Colacino, E. (2014). Solventless mechanosynthesis of N-protected amino esters. The Journal of Organic Chemistry, 79(9), 4008–4017.
Lacorn, M., & Hektor, T. (2018). Determination of ethanol in kombucha, juices, and alcohol-free beer by EnzytecTMLiquid Ethanol: Single-laboratory validation, First action 2017.07. Journal of AOAC INTERNATIONAL, 101(4), 1101–1111.
Lutmer, B., Zurfluh, C., & Long, C. (2009). Potential effect of alcohol content in energy drinks on breath alcohol testing. Journal of Analytical Toxicology, 33(3), 167–169.
Park, S., Kim, J.-C., Lee, H. S., Jeong, S.-W., & Shim, Y.-S. (2016). Determination of five alcohol compounds in fermented Korean foods via simple liquid extraction with dimethyl-sulfoxide followed by gas chromatography-mass spectrometry for Halal food certification. LWT - Food Science & Technology, 74, 563–570.
Russian news agency. (2021, October 10). Death toll from methanol poisoning in Russia’s southern Urals up to 34. https://tass.com/emergencies/1347697?utm_source=google.com&utm_medium=organic&utm_campaign=google.com&utm_referrer=google.com
Schultz, K., & Kumar, H. (2019, February 23). Over 90 Killed in India by Toxic Homemade Liquor. The New York Times. https://www.nytimes.com/2019/02/23/world/asia/india-poison-alcohol.html
Susparini, N. T., Abidin, Z., Pradono, D. I., & Nurhidayat, N. (2019). Sensitive and stable ethanol biosensor development based on Acetobacter aceti biofilm for halal detection of food and beverages. Journal of Applied Biology & Biotechnology, 7(6), 40–47.
van den Broek, J., Abegg, S., Pratsinis, S. E., & Güntner, A. T. (2019). Highly selective detection of methanol over ethanol by a handheld gas sensor. Nature Communications, 10(1), 4220.
Verplaetse, T. L., & McKee, S. A. (2017). An overview of alcohol and tobacco/nicotine interactions in the human laboratory. The American Journal of Drug and Alcohol Abuse, 43(2), 186–196.
Vojvodić, S., Čonić, B. S., & Torović, L. (2023). Safety assessment of herbal food supplements: Ethanol and residual solvents associated risk. Journal of Food Composition and Analysis, 122, 105483.
Watson, R. R., Preedy, V. R., & Zibadi, S. (Eds.). (2013). Alcohol, Nutrition, and Health Consequences. Humana Press. https://doi.org/10.1007/978-1-62703-047-2
Yarita, T., Nakajima, R., Otsuka, S., Ihara, T. A., Takatsu, A., & Shibukawa, M. (2002). Determination of ethanol in alcoholic beverages by high-performance liquid chromatography-flame ionization detection using pure water as mobile phase. Journal of Chromatography. A, 976(1–2), 387–391.
Zhang, Y., Chen, Y., & Chen, J. (2022). The starch hydrolysis and aroma retention caused by salivary α-amylase during oral processing of food. Current Opinion in Food Science, 43, 237–245.
)