If you eat a piece of chocolate while chewing gum, will the gum disappear?

When you are not hungry but always want to chew something, would you choose chewing gum? Chewing gum can not only clean your mouth, but also relieve anxiety and stress. But after chewing for a long time, the gum will become less and less flavorful and harder. At this time, you may start looking for new food. If you have not spit out the chewing gum in your mouth and eat a piece of chocolate, then a magical thing will happen - the chewing gum will gradually soften, and finally disappear in your mouth as if it melted! Why is this?

01 Fat-soluble gum base: Solving the mystery of the disappearance of chewing gum

Take any kind of chewing gum and look at its ingredient list. You will find that chewing gum is mainly composed of gum base, sweeteners, flavors and other ingredients. The gum base here is a rubber-like substance with good elasticity and toughness, and can be chewed repeatedly. Initially, people used latex secreted by some trees as a natural source of gum base. With the development of industry, people gradually used synthetic resins to replace natural gum to produce chewing gum.

Common chewing gum ingredients: Gum base is the main ingredient Source: Taobao

Whether it is natural gum base or synthetic gum base, they are essentially a type of high-molecular long-chain polymer containing a large amount of carbon and hydrogen elements. They are generally insoluble in water , so they will not be dissolved by saliva and can withstand repeated chewing.

A polymer molecule is a long chain consisting of many repeated monomers connected end to end. Image source: clearwaterind.com

However, gum base is fat-soluble , which means that gum base is easily soluble in solvents such as oils and fats. Chocolate contains a lot of cocoa butter, which is an edible oil extracted from natural cocoa beans. Therefore, when chewing gum and chocolate together, the gum base in the gum will dissolve when it encounters cocoa butter and eventually disappear in the mouth. So why is gum base difficult to dissolve in water but easy to dissolve in oils and fats? Why can the solubility properties of substances be completely different for different solvents?

02 Principle of like dissolves like: things with the same properties can blend with each other

This brings us to the principle of like dissolves like - an empirical law about the solubility of substances. At the microscopic level, the molecules of a substance will carry certain positive and negative charges. When the centers of the positive and negative charges coincide, the charge is evenly and symmetrically distributed from the perspective of the molecule as a whole, and this molecule is called a non-polar molecule . On the contrary, if the centers of the positive and negative charges do not coincide, this molecule is called a polar molecule , and its charge distribution is uneven and asymmetrical.

Schematic diagram of nonpolar molecules and polar molecules Source: chem.libretexts.org

The principle of like dissolves like means that solutes composed of polar molecules are easily soluble in solvents composed of polar molecules, but are difficult to dissolve in solvents composed of non-polar molecules; while solutes composed of non-polar molecules are easily soluble in solvents composed of non-polar molecules, but are difficult to dissolve in solvents composed of polar molecules . Is it a bit confusing? You can understand it this way: the solute and solvent are easy to dissolve only when their properties are the same (that is, when they are both polar or non-polar) , and are difficult to dissolve if they are different . This is just like being in a relationship, two people need to be in tune with each other to get along well, and if they have personality conflicts, they will definitely not get along.

Illustration of the principle of like dissolves like: solutes and solvents with similar properties are easily soluble. Image source: drawn by the author

Water and alcohol are typical polar solvents, while various oils and fats are mostly non-polar solvents. The long-chain molecules of many polymers are non-polar, such as the gum base in chewing gum, so it is difficult to dissolve in water, but easily soluble in cocoa butter. There are many substances with similar properties in life, such as carotene. When you fry carrots with oil, you will find that the oil in the pan will turn yellowish red. However, when you blanch the carrots, the remaining water has no color. This is because carotene is a fat-soluble pigment that can be dissolved by edible oil but difficult to dissolve in water.

Oil dissolves carotene, showing a yellowish-reddish color. Source: Xiaohongshu. There are many other non-polar solvents, such as benzene, carbon tetrachloride, liquid paraffin, esters, ethers, etc. Many times, for some dirt that is difficult to wipe off with water, these non-polar solvents can be used to quickly remove it, which is a miraculous effect.

03Universal Fengyoujing: Life tips based on the principle of like dissolves like

Families with children may encounter such troubles: children like to draw everywhere in the house with markers, and their masterpieces can be seen on the floor, countertops, and cabinets. Many markers are oily, and it is difficult to remove the marks after a while. At this time, you only need a small bottle of Fengyoujing to help you solve the problem. The ingredients such as methyl salicylate and eucalyptus oil contained in Fengyoujing are non-polar solvents . According to the principle of like dissolves like, it can dissolve the oily ink of the marker, and then it can be cleaned up with a wipe.

Netizens try to use Fengyoujing to remove marker pen marks and residual offset printing. Image source: Xiaohongshu. In addition, if you want to clean old stubborn offset printing, you can also apply some Fengyoujing and then wipe it hard, because the residual glue is also a high molecular polymer, which is also easily soluble in non-polar solvents .

04 Should I worry if I accidentally swallowed gum?

There is a widely circulated saying that chewing gum will stick to the intestines if swallowed. Have you ever panicked after accidentally swallowing chewing gum?

Image source: Photo Network

In fact, you don’t have to worry too much. First of all, the gum base of chewing gum cannot be digested by stomach acid or enzymes . In addition, the inner wall of the stomach and intestines is very smooth and secretes a lot of mucus, which will prevent undigested chewing gum from staying on it. As the intestines move, it will move along the digestive tract and eventually be excreted from the body . Although there is no need to worry too much, it is still not recommended that you swallow chewing gum, especially for children, whose digestive tracts are much smaller than those of adults and are likely to be blocked by chewing gum. Finally, curious friends can try what chewing gum tastes like with chocolate, but it is not guaranteed to be delicious~ Author: Wei Anran, application engineer, Ph.D. in mechanics, Shanghai Jiao Tong University

Editor: Tinker Bell