First, honey is a kind of sugar. Sugar is hygroscopic, which means that in the natural state, sugar contains very little water, natural honey water content is only about 18%, the rest is all sugar, so honey is a saturated hypertonic high-sugar solution. Bacteria and other biological body fluids are hypotonic, and in honey with high osmotic pressure, microbes will be sucked out of the cells and eventually dehydrate and die.
At the same time, honey is very sour. The optimal PH for most pathogens to grow and reproduce is between 7.2 and 7.4, while the PH of honey is about 3 to 4.5, and the acidity of honey will kill any bacteria that want to grow inside the honey.
High acidity and concentration make honey not an ideal place for microorganisms to inhabit, which is conducive to the long-term preservation of honey. However, honey is not the only type of sugar that absorbs moisture. Syrup made from sucrose is also very hygroscopic, although the PH is lower than that of honey, about 5.5, but it is also acidic, so why does the syrup spoil over time?
This brings us to the honey maker, the bee.
Before bees make honey, they need to collect nectar from plant nectars, the main components of nectar are sucrose and water, and the water is very much, accounting for about 60% to 80%. But by making honey, bees can remove most of the water from the nectar.One of the most important processes is rumination. When the bees collect honey, they will inhale the nectar drop by drop into the pocket, and then return to the hive, spit out to the domestic bees to continue processing. In the process, the internal bees suck the honey into their stomach and the invertase mix, and then spit it out, and then suck it in, so the rotation of more than 100 times, while other bees will continue to fan the wings to discharge the moisture in the nest. At this time, the nectar will continue to evaporate water. Honeybees, on the other hand, have an enzyme called glucose oxidase in their stomachs. When bees regurgitate nectar from their mouths to the hive to make it, the enzyme chemically reacts with the nectar, breaking it down into two byproducts: gluconic acid and hydrogen peroxide.
Hydrogen peroxide is another important reason why honey lasts so long. Hydrogen peroxide, which is an oxide of hydrogen, may sound a little strange, but when it comes to hydrogen peroxide, it's probably very familiar to everyone. Highly oxidized and weakly acidic, hydrogen peroxide kills any bacteria that might grow in honey and was used as a biological weapon by Nazi Germany in concentration camps during World War II.
In ancient times, because honey is a bacterial "insulator" and contains hydrogen peroxide, it became the perfect "natural band-aid" to prevent wound infections. The medical use of honey was first recorded on Semitic clayboards, which detail how honey was used to treat burns and cuts. The ancient Egyptians also often used medicinal honey to make ointments to treat skin and eye diseases. In China, honey pills are still one of the most commonly used preparations in the pharmaceutical industry. A bandage coated with honey is still used in hospitals around the world to keep patients' wounds from getting infected.
Of course, although honey is an immortal food and has therapeutic effects, if it is not sealed well, it will still deteriorate in a humid environment, and if it is sealed well, it will never deteriorate.