Food safetyRapid, on-site detection of illegal cooking oils
In recent years, illegal cooking oil incident in China caused serious food safety risks. Researchers have developed two rapid and convenient colorimetric detection methods of illegal cooking oils based on phase transfer technology.
Removing processed waste oil from supermarket shelves // Source: xzone.vn
In recent years, illegal cooking oil incident in China caused serious food safety risks. Professor H. E. Yujian and his group from College of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, have developed two rapid and convenient colorimetric detection methods of illegal cooking oils based on phase transfer technology. This work could be helpful for rapid and on-site detection of illegal cooking oil. Their work was published on Science China Chemistry.
Science China Press reports that illegal cooking oil includes refining of waste oil from restaurant, repeatedly used oil and, the use of waste animal fats. Because illegal cooking oil may contain toxic polymer, peroxide, and more, it is dangerous to human health. The most common clinical symptoms of poisoning include headache, vomiting, diarrhea, and abdominal pain. Recently, illegal cooking oil found its way into family kitchens, leading to serious food safety risks in China. Government monitoring, purchase records, and granting licenses can be used to control the problem of illegal cooking oil, but rapid and on-site detection of illegal cooking oil is still necessary.
The detection method developed by Professor H. E. and colleagues is based on phase transfer technology. The copper ions and cationic gold nanoparticles protected by poly (diallyl dimethylammonium) chloride (PDDA) were used as the recognition probes. The illegal cooking oil could be detected by naked eye. The results showed that qualified cooking oil mixed with 2.8 percent of illegal cooking oil could be detected, and more than 5 percent of illegal cooking oil could be accurately detected by the naked eye. These methods were applied in blind test for a total of 235 samples; the results showed that the accuracy rates of the blind tests to be 95.7 percent.
Compared with the traditional methods, this method is cost-effective, allowing for rapid and simple colorimetric detection of illegal cooking oils without complex pre-treatment.
The work could be beneficial for the rapid on-site detection of illegal cooking oil. It has the potential of being implemented in civilian fields because of its high accuracy, simplicity, and low cost.
The research findings are part of a national patent application.
— Read more in Yuan LongFey et al., “Rapid colorimetric detection of illegal cooking oils based on phase transfer technology,” Science China Chemistry 7 (2013) (doi: 10.1360/032012-459)
