With the improvement of people's living standards and the increasing emphasis on dietary health, the storage requirements for fresh food at home are getting higher and higher. At present, the commonly used storage methods fo fresh food at home include low-temperature storage, high-temperature storage, and dehydration storage.
The most commonly used cryopreservation is the refrigerator. Low temperature can reduce or stop the reproduction speed of microorganisms in food and slow down all chemical reactions in food, but it cannot kill microorganisms, and can only greatly reduce the effect of microorganisms on food. However, the fat in food still cannot avoid rancidity and deterioration. High-temperature storage kills most of the microorganisms in the food by heating such as boiling, and destroys the enzymes in the food; however, if it is not stored properly, it is extremely susceptible to microbial contamination and accidents. Dehydration preservation is to reduce the moisture content in food to a certain limit, making it difficult for microorganisms to reproduce and inhibiting the activity of enzymes, thereby preventing food spoilage, but the dehydration efficiency is low, and it cannot effectively kill microorganisms and bacteria.
Compared with the above-mentioned home fresh food storage methods, vacuum freeze drying technology has obvious advantages. Vacuum freeze drying technology uses the sublimation of water for drying. Seasonal fresh food can use vacuum freeze-drying technology to retain the original nutrients, which will be more convenient for long-term storage, avoid waste, and make food easy to eat and taste good. How to use a home freeze dryer machine? Let's introduce:
How to use a mini freeze dryer machine?
- Before freeze drying your food, be sure to choose the freshest. Wash your food to remove any particles, dirt and contamination. Then, cut the food into small or large pieces to remove the water.
- After placing the pretreated food evenly on the food tray, place it on the food rack. The food tray material is food-grade stainless steel, which is safe and hygienic, and the surface is smooth and easy to clean.
- After the one-key start, the pre-cooling treatment is first performed, and the pre-treatment is completed by the refrigeration system. The refrigerant in the refrigeration system is compressed by the compressor and becomes a high-temperature and high-pressure gas, which becomes a high-pressure liquid after being cooled by the condenser, and then becomes a low-pressure liquid through the expansion valve in the refrigeration system and then enters the evaporator outside the freeze-drying box. The evaporation of the refrigerant absorbs the heat in the freeze-drying box to achieve the purpose of cooling.
- The evaporated refrigerant turns into a low-pressure gas and enters the compressor again for the next cooling cycle.
- When the temperature of the food in the freeze-drying box is completely lowered to the set temperature, the vacuum system will be activated.
- After the vacuum pump works, the air in the freeze-drying box is pulled out through the corresponding pipe fittings to reduce the gas pressure inside the freeze-drying box. The vacuum system will continue to operate until the lyophilization process is complete.
- When the gas pressure inside the freeze-drying box is reduced to the set value, the heater will be turned on. Through the work of the heater, the temperature of the food is raised to the set value, the moisture inside the food is sublimated, and the drying process is carried out.
- When the food freeze-drying process is completed, the machine will automatically stop and remind the user through sound and light.
- After the freeze-drying process is completed, the food tray can be directly taken out and stored in separate packaging.
Advantages of home freeze dryers:
- The household freeze dryer has a compact structure and a reasonable layout, which can easily handle fresh food and meet household needs. This product can process about 7 liters of food at a time and can process different foods at the same time in the same batch, such as strawberries and corn at the same time.
- The vacuum freeze-drying technology is used to prolong the storage time of food and preserve the nutrients of the food to the greatest extent.
- It can handle fresh food conveniently, avoid the waste of seasonal fresh food that cannot be processed in time, and keep the original color, aroma, and taste of fresh food to the greatest extent, so that the food is convenient to eat and tastes good. If the natural pigment of vegetables remains unchanged, the loss of various aromatic substances can be reduced to a minimum;
- The drying process avoids the loss of nutrients that are easily produced by general drying methods. It can preserve various nutrients in food (such as protein, vitamins, phytonutrients, etc.), especially vitamin C, can preserve more than 90%, especially suitable for heat-sensitive substances, and can make heat-sensitive materials dry and retain heat-sensitive ingredients.
- During the drying process, the growth of microorganisms and the action of enzymes cannot be carried out, so the original characters can be maintained.
- The food processed by freeze drying is light in weight, small in size, occupies less space during storage, is easy to carry and transport, and has low freight. Such as various freeze-dried vegetables are briqueted, and the weight is reduced significantly. Due to the reduced volume, the packaging costs are correspondingly much less.
- The dried food is quick to rehydrate, easy to eat, and has no surface hardening and drying phenomenon. The rehydration and instant solubility are greatly improved, the rehydration rate is over 90%, and the rehydration time is greatly shortened; because the moisture contained in the dried material is directly evaporated in the freezing state, so in the drying process, the water vapor does not drive soluble substances Move to the surface of the material, no salt will be deposited on the surface of the material, that is, no hard thin skin will be formed on the surface of the material, and there will be no tension on the cells or fibers when the central moisture moves to the surface of the material, and the material will not be dried. Because of the deformation caused by shrinkage, it is easy to absorb water to restore the original shape.
- Freeze-dried food can remove 95% to 99% of the moisture, without adding preservatives, etc., so that the dried food can be stored for a long time without deterioration.