With the fast life rhythm nowadays, freezer is a good electrical product for storing food, but we can not say that all the food stored in the freezer is healthy, especially the freezer in the supermarket with has been used for long time use without cleaning regularly, the freezer itself causes a lot of bacterium, and it will contaminate the food inside. Although the food looks fresh, actually it has gone bad.
Commonly, the temperature between 4 to 8 ℃ is used to keep food in a cold storage, the growth speed of vast majority of bacterium will slow down in this condition. But some are psychrophilic bacteria, such as Yale sen bacteria, Listeria monocytogenes ,they have a rapid growth and breed under this temperature .If the food in the freezer is infected with these bacterium, it could cause intestinal disease. And with the temperature of -18 ℃ in the freezer,general bacterium will be inhibited or killed, so there is a better preservation effect if you store food inside the freezer . But freezing does not equal to Kill germs completely , still some bacterium with stronger antifreeze ability can survive. So, from another point of view, if you don't often do some disinfection, it will become a cradle for some kinds of bacterium.
The time for food keeping in the freezer could not be too long though. And you have better to eat up the food after buying it from the supermarket, because the prolong storage time will affect both the taste of the food and easily get a strange smell. There are some fruits like bananas or apples, they will get metamorphic if you keep it for a long time,once they get metamorphic they will send out a kind of harmful gas.Another thing is that you are not supposed to put too much food in the freezer ,because it will lead to the deterioration of the food with different temperature among the great amount of food.
The refrigeration of the freezer is rely on the rotation of the compressor.Due to the principle of electromagnetic induction, the motor rotation will produce certain electromagnetic, and formed a certain electrostatic voltage on the shell. Any kind of household electrical appliances with sensing elements (including TV, air conditioner and other household appliances), so long as the freezer doesn't have the ground connection there will be certain electrostatic voltage at he moment when you turn on or turn off the machine.(same as the TV screen in the switch moment). Due to the electrostatic voltage power itself is very small, therefore ,there is no harm to human body. Nonetheless, freezers, as a kind of electrical appliances,a reliable grounding state in case of the failure of its insulation performance,there is the risk of electric shock then. Therefore installing the grounding line is very necessary, is also a must.
