In our daily life, we often use alcohol as a disinfectant.
But is alcohol a suitable substance to kill bacteria or mold?
First, let’s distinguish the difference between bacteria and mold!
Bacteria belong to prokaryote, most organisms nowadays in the world evolved from bacterial prokaryote.
The environment around us is full of bacteria, bacteria grow very fast in a humid environment. It has a structure called flagellum that let it able to swim, so it is very suitable for them to live in water.
The advantage of bacteria is the growing speed. Especially Escherichia coli, it will split and reproduce every 20 minutes, 1 splits into 2, 2 split into 4, 4 split into 8… In only one day, 2^72 Escherichia coli will be produced which is 472,236 trillion bacteria, the splitting speed is amazing! Like clothes, if you don’t dry it right after washing, it will be stink, which is caused by bacteria that likes high humidity and reproduces fast. Raw meat is rich in moisture by itself. Therefore, keeping meat fresh is mainly to prevent the rapid growth of bacteria, not to prevent molds.
Molds belong to eukaryote. Through spores, hyphae and other structures, mold can reproduce and penetrate the surface of the object to absorb nutrients. Most species of molds prefer high humidity (about RH 60-99%) but not an environment with water, and also suitable temperature (25～35℃.) Mold spores are like plant’s seeds. It is easy to resist bad environment, and wait for the right timing to sprout. The structure of mold’s cells is more complex than bacteria. Therefore, they can’t grow as fast as bacteria. The mold grows slowly, it takes at least 6 hours for the spores from fall to sprout. And it takes 3 days to become visible with naked eye.
So, is alcohol a suitable substance to kill both bacteria and mold?
Alcohol is used to dissolve lipid-face surfaces. When it evaporates, it will take away the moisture on the surface at the same time. The bacteria with a simple external structure are easily penetrated by alcohol, and the moisture is taken away, causing dehydration and death, achieving the effect of killing bacteria. By the way, spraying alcohol on your hands will dry your hands because the alcohol takes away moisture while evaporating.