In the circle of friends, there was a video entitled “Beverages will change color when the paper towel is stirred”. Video display: Add filter paper to a cup of yellow drink, stir it for a while and then remove the filter paper. As a result, the filter paper turns yellow and the beverage completely loses its color! Many people exclaimed, so scary, no more drinks in the future!

What is the reason for the beverage to completely fade? The color of the drink in the video comes mainly from lemon yellow and sunset yellow, which are two synthetic pigments widely used in food. The filter paper has a good adsorption effect on them. After being fully stirred, they will be adsorbed from the water onto the filter paper, and the beverage will lose yellow color.

This is a very common physical phenomenon, and its principle is similar to the decolorization of activated carbon in the grain and oil industry. In general, pigments, whether natural or synthetic, are easily adsorbed by a filter paper having good adsorptivity or adsorbed by a filter, and "decolorized" from a colored beverage.

Of course, the problem that ordinary consumers care about is often: What is pigment? Why do you want to add color to food? Is pigment harmful to health?

"Selling bad", many people may lose the desire to try

Some experts often say that pigments only improve the visual effect of food, and do not have any nutritional value, but also bring harm to the body.

This statement is not wrong in itself, but it is not comprehensive. Studies have shown that for most people, the color of the food affects their perception of taste. The color of the food is the first element of the human body. If the "selling is not good", many people may directly lose the desire to try.

Modern society pursues the standardization of commodities. For the food industry, the difference in raw materials will result in slightly different colors of finished products. If it is a home-made or restaurant-made food, this difference will not be too much of a problem, but in processed foods, it is difficult to accept. The same kind of food bought yesterday can be seen differently from the naked eye bought today. Most consumers will inevitably doubt the quality of the product.

Is it safe to be a synthetic pigment for "food coloring"?

Natural pigments are food colors obtained from natural sources, and synthetic pigments are artificially synthesized pigments.

In fact, natural pigments are still extracted through chemical processes, not "natural" that many people imagine. In addition, natural pigments are expensive to produce and expensive, but they are often not stable enough to fade during food processing and storage. Synthetic pigments clearly have great advantages in terms of production cost and color stability.

In the United States, there are only nine synthetic pigments that are allowed to be used, and their management is more stringent than other food additives. At present, there are only a few basic synthetic pigments in the world that can be used in food. Different colors are blended through these basic colors.

There are many substances that can dye food, but in order to become a "food coloring", extensive safety assessment is required. Generally, by feeding different amounts of experimental animals for a long time, find the maximum dose without any abnormality, and divide this dose by a large "safety factor" (usually 100 or higher) as a safe intake of the human body. the amount. Based on this safety ceiling and the maximum amount of food a person may consume each day, the maximum amount allowed in that food is determined.

The safety standards thus formulated are actually quite rigorous, but people and animals are different after all, and uncertainty always exists. For the approval of the pigments that can be used, long-term tracking and later modification are still required.

In the 1970s, a pediatrician declared that children's behavior was related to the intake of food pigments. The US FDA reviewed the scientific literature at the time and concluded that synthetic pigments "may" have an adverse effect on some children, but the evidence is not sufficient, so more research is needed to make further decisions on synthetic pigments.

Until 2007, the results of the University of Southampton in the United Kingdom showed that some pigments may cause children's attention to decline and hyperactivity in some cases, but the European Food Safety Commission (EFSA) reviewed the study and concluded that it is not enough to be a change. The rationale for these synthetic pigments and sodium benzoate safety standards. In 2009, EFSA lowered the safety ceiling for three of the six pigments involved in the Southampton study.

In fact, impurities that may be present in the pigment are more important than the pigment itself. In the United States, the safety approval of pigments is carried out in batches. That is to say, every time a manufacturer produces a batch of products, the samples are sent for testing, and they are qualified before they can be sold by the FDA.

Safety premise for synthetic pigments: whether it is a "qualified product"

The United States has evaluated residents' synthetic pigment intake and concluded that the average American intake is far below the safety ceiling. Even if the intake reaches 10 times the national average, it is still well below the safety ceiling.

In China, the six pigments used in the study in Southampton were allowed. Considering that the amount of processed foods in the Chinese population is much less than that in the United States, the total amount of food intake may be far from the “excessive standard”. The synthetic pigment itself is safe, but only if it is a "qualified product".

In general, the use of pigments is often accompanied by high carbohydrates, deep processing, and low nutrient density. Allowing children to reduce the consumption of such foods or beverages and getting used to the "truth" of food helps children develop good eating habits and is more likely to achieve a comprehensive balance of nutrition.