Understand the cellar of few people, cellar storage vegetables compared to the refrigerator has what advantages?

In the countryside, in winter, cellars are dug to store vegetables, the ground is cold and frozen, but inside the cellar is particularly warm. Vegetables in the cellar are kept at a certain temperature, which means they won't rot because the temperature is too high. When I was a child, my family dug a cellar, and the vegetable cellar was relatively shallow. In winter, we ate more cabbages and potatoes, which were more frost-resistant, and dug a shallow one for easy storage. Cellar for storing sweet potatoes, apples, etc. It is very deep, so it is often necessary to dig a very high room, and the things placed in it will not break next spring. For thousands of years, our ancestors used the cellar method to store grains. Cellars for storing grain were found as early as the prehistoric site of Mount Magi in Wuan, Hebei Province. The winter was cold and fresh vegetables were not available, so we had to stock up on grain in advance. The temperature in the cellar is relatively stable, and it is most suitable for storing potatoes, cabbages and radishes, and then taking them out and filling them up when they are cool.

Digging a cellar is hard work. Different sizes of cellars are usually dug depending on the number of people in the family and their needs. There are round cellars and square cellars. Smaller round cellars are usually sweet potato cellars and the like. They are small and can store little food. In contrast, square wine cellars can be slightly larger and have a wider range of movement. A ladder is usually placed at the mouth of the cellar to make it easier to get up and down. The depth of the cellar is mostly more than two meters, which can provide a good constant temperature. The mouth of the cellar is covered with wooden or stone boards, and sometimes a thick layer of straw. The temperature of the cellar is kept at about 0-5 degrees. Different kinds of vegetables are placed separately. Usually potatoes, sweet potatoes and turnips are placed at the bottom and cabbages at the top of the shelves. There is regular ventilation and organization, which can be worn for a long time. Large vegetable cellars are basically red brick with lighting.

The cellar method is often used because of the thicker dry soil in the north. Because of the soil's weak thermal conductivity, its temperature varies much less than the atmosphere. In winter when it is too cold outside, it is good for heat preservation. In the fall or early winter, when the outside temperature is too high, the temperature inside the cellar can still be kept low, and the change of humidity in the soil is relatively stable, which is conducive to preventing fruit withering. In addition, the gas exchange in the soil is poor, and the cellar is usually covered with mulch, so the cellar has a natural coordinated function of accumulating carbon dioxide and reducing oxygen, which ensures that the food does not deteriorate for a long time! Low temperature has always been the king of preserving food because bacteria have weak life activity and low reproduction capacity at low temperatures. Under the low temperature conditions of ice and snow in winter, heaven and earth are a big refrigerator, and there is no problem with natural preservation. In summer, it can be cool deep underground, so the ancients also hid their food in a very deep non-concrete cellar to keep it fresh.