Napkin adsorption of beverage color is not equal to beverage coloring

“Pour the orange soda drink into the glass, then put it on a napkin and stir it quickly. After 1 minute, the drink in the cup is white, and the paper towel has turned orange.” Recently, such a “ The video of the beverage will fade after being stirred by a napkin. The video is transmitted on the Internet. Experts say that napkins do have the effect of adsorbing pigments, but this experiment does not prove that the pigments in the beverages are excessive.

To prove the authenticity of the experiment in the video, the reporter purchased Mei Nida, napkins, wet tissue and freshly squeezed orange juice for experiments. First, pour the Mynida drink into the cup and put in a napkin and start stirring. During the mixing process, the napkin gradually changed from white to orange. After 1 minute, the orange color of the napkin was very noticeable. After that, the reporter added three napkins in turn to the cup, each stirring for 1 minute. After using the fourth napkin, the color of the beauty of the cup was significantly lighter and golden yellow, in stark contrast to the original orange, but did not achieve the "transparent" effect in the video. The reporter used the wet tissue paper to do the same experiment. After 1 minute of stirring, although the wet tissue paper was also attached with obvious orange color, no matter whether it was from the color of the paper towel or the color of the cup in the color of the cup, there was no napkin test. After the effect is obvious. So, will experimenting with freshly squeezed juice that is not added with pigments the same effect? After the reporter removed the two oranges from the skin, they placed them directly into the juicer to make a glass of orange juice. According to the same experimental procedure, although there is color change on the napkin, it is different from the previous Mei Ning experiment. The paper towel soaked and stirred by Mei Nida is orange in color, and the color of the paper towel soaked in freshly squeezed orange juice. It is yellow and the color distribution is not uniform.

In this regard, Li Meiping, a professor of food science and engineering at Shanxi University, said that the above experiment can only indicate that the napkin has an adsorption effect on the pigment, but it cannot prove that the pigment content in the beverage is too high. The pigments are basically divided into two types, one is a natural pigment, such as a pigment extracted from fruits, and the other is a synthetic pigment, that is, an organic pigment obtained by an artificial chemical synthesis method, and the pigment added to the beverage is mostly This class. Napkin paper has many micropores and voids, and the synthetic pigment particles are larger than the natural pigment particles in the freshly squeezed juice, and are more easily adsorbed on the napkin, so the effect of the freshly squeezed juice experiment is not as obvious as the beverage. However, if the beverage is prepared by artificially extracted natural pigments, the particles are relatively large, so the experimental effect is similar to that of the artificial synthetic pigment beverage. Li Meiping said that the use of artificial synthetic pigments within the prescribed range will not affect the human body, but children and young children are in the stage of growth and development, and drink less beverages containing pigments.