The invention provides a method of measuring multiple
preservative, sweetener and colorant in food at the same time. The method comprises the following steps of 1, weighing and taking 5-10 g of a sample and placing the sample into a color comparison tube of 50 ml, adding water and dissolving the sample, implementing ultrasonic extraction for 30 minutes, if the
protein content is high, needing to add a
protein precipitant to regulate the pH value to be neutral, adding water to implement constant volume, mixing evenly, and flowing through a microporous membrane of 0.45
micrometer for use; 2, taking a sample solution to implement liquid chromatographic analysis, and calculating and obtaining
preservative, sweetener and colorant contents in the sample to be measured against a
standard curve. According to the method of measuring multiple
preservative, sweetener and colorant in food at the same time, multiple preservatives, sweeteners and colorants in food can be measured at the same time, the accuracy rate and
recovery rate of measured samples are guaranteed, it is ensured that the
relative standard deviation is in an allowable range, the applicable range of the method is also ensured, the experiment efficiency is improved, and the laboratory cost is saved.