According to China's food safety standards, except wine, vinegar, solid sugar, salt and monosodium glutamate whose temperature is above 10, all other foods must be marked with shelf life, and honey is no exception. In the market, we often see that the shelf life of honey is two years.
Although the shelf life of honey is two years, honey can still be eaten after long-term storage. In the last century 10, American scientists found a jar of honey in the pyramids of Egypt. This bottle of honey was buried with the pharaohs of Egypt, with a history of at least 3,000 years. However, scientists have found that this bottle of honey has not been corrupted so far, which means that honey can actually be preserved for a long time.
When bees brew honey, they go back and forth between flowers and nests every day. When bees collect honey, they will fill the honey sac and then return to the nest. At this time, nectar will also be converted into honey. Then return to the nest, and when the honey is not fully mature, spit the honey back into the nest. When looking after nectar, bees will constantly flap their wings to accelerate the evaporation of water in honey and form mature honey. The ratio of mature honey to initial honey is 0.2: 1. When ripe honey fills the hive, bees will seal the honey room with beeswax.
Pure mature honey has high concentration and osmotic pressure, which can resist microorganisms and dehydrate invading microorganisms and die. So honey at this time can be preserved in a dry environment for a long time.
However, if the honey is not properly preserved, the preservation effect may be greatly reduced. First of all, honey can't be stored in the open air, because the substances in honey can easily absorb the moisture in the air, which leads to the decrease of honey concentration. When the concentration of honey is reduced to a certain extent, microorganisms can survive here. The most common is the acid swelling of honey, which is the acidic substance and carbon dioxide formed after the microorganism decomposes honey.
The optimum storage temperature of honey is 5℃- 10℃, and it needs to be stored in a dry and ventilated environment without direct sunlight.
The honey in the pyramid can be preserved for thousands of years. It is precisely because the air in the pyramid environment is dry and the honey is sealed in a jar, so the honey is difficult to be decomposed by microorganisms. 、
Honey is rich in nutrients and sugar, and contains monosaccharides such as glucose and fructose that can be directly absorbed by the human body. However, the nutrients in honey are not resistant to high temperature and need to be brewed with warm water below 40℃.
Why does the honey I bought expire?
Mature honey can be preserved for decades under good preservation conditions, but some people will find that the honey bought not long ago is sour. This is not only related to the source and improper preservation of honey, but also related to the quality of honey.
Honey is divided into water honey and mature honey. Among them, honey is honey brewed for about 3 days, so the water content is high, so it is called "water honey". Mature honey is brewed for about 7- 10 days (depending on the external temperature), and the honey contains little water, so the honey at this time is "mature honey" and can be preserved for many years.
Compared with mature honey, water honey has low nutritional value and high moisture content, and is more prone to deterioration. Drink it as soon as possible after buying it.
Baume degree is a way to measure the quality of honey. Generally speaking, honey with a Baume degree of about 43 is mature honey, and honey with a Baume degree of about 39 or even lower is water honey. However, some merchants will evaporate the water from the bought honey at high temperature to make concentrated honey. However, in the process of concentration, active substances are easily destroyed and have low nutritional value.
It is said that there is an indigenous method to test whether the purchased honey is really mature honey or concentrated honey, that is, add some honey to the bottle and shake it vigorously. If there is abundant foam, it is honey; if there is no abundant foam, it is concentrated honey.
Many people know that beekeepers will feed honey to bees in winter when there are few honey sources, so many people worry that some beekeepers will pass off white sugar as honey. In fact, we don't have to worry about this, because the price of white sugar is high, and the cost of feeding bees every day is very high. During the epidemic this year, traffic control in many places did not allow casual travel, so that many beekeepers would die in a large area if they did not collect honey in another place. So in general, we don't buy bees cultivated with white sugar. After all, it is not cost-effective in terms of input-output ratio.
abstract
The preservation of honey needs a dry environment, and it is best to seal it after eating honey every time. Sometimes, when some bees collect honey, the local humidity is high, which leads to more water in mature honey. At this time, honey is also easy to deteriorate and needs to be drunk as soon as possible.