A video has been circulating online recently, where someone repeatedly washes purchased noodles with water, resulting in a sticky "gel" after washing. This has led to speculation that plasticizers or some kind of glue have been added to these noodles. Is this really the case?
The chewy texture of noodles comes from gluten, which is the protein in flour. The sticky stuff left after repeatedly washing the noodles in the video is exactly that.
To make noodles chewy, you can add some ingredients, such as vital wheat gluten powder, eggs, salt, or alkali.
The claim that plasticizers are added to noodles might be a rumor, but the addition of glue is quite common. This "glue" is not an industrial adhesive, but an edible one, scientifically known as a thickener, also called soluble dietary fiber.
Currently, there are dozens of thickeners approved for use in the country, many of which are extracted from natural foods. For example, alginic acid, carrageenan, etc., extracted from seaweed. Some are also produced from starch through microbial fermentation, such as cyclodextrin, curdlan, xanthan gum, etc.
Take xanthan gum, the most commonly used thickener, for example. It is a high-molecular-weight polysaccharide that can improve the toughness of noodles. At the same time, it has high viscosity and good solubility, and can absorb a large amount of water, making the noodles more elastic and smoother in texture.
So, chewy noodles do require some technical processing, but it's not some kind of "black technology".