Researchers developed a quick and easy method to detect nitrate and nitrite in food using flow injection analysis. They found that the method accurately detected nitrate levels ranging from 20.0 to 2000.0μg/L and nitrite levels ranging from 2.0 to 200.0μg/L. The detection limits for nitrate and nitrite were 1.1μg/L and 0.4μg/L, respectively. The method had a high sample throughput, with the ability to analyze 22 samples of nitrate and 27 samples of nitrite per hour. The results showed that the method was effective in determining nitrate and nitrite levels in food samples.