Freeze dryer China reaches long-term transportation standards by drying the moisture content of vegetables and fruits

Freeze dryer China reaches long-term transportation standards by drying the moisture content of vegetables and fruits
Vegetables and fruits are subject to freeze-drying technology to reduce water content, low temperature prevents microorganisms from multiplying, and enzymes in vegetables and fruits produce inertia, so that vegetables and fruits can be stored for a long time and easy to transport for a long time.
1. Dry air
The mechanism of China skill of freeze dryer is the same as that of boring of other conventional materials. Its main feature is the use of hot air with suitable temperature and air volume to promote the outward dispersion of moisture inside the pistil through the capillary. Because atmospheric pressure hot air skills have been selected, both domestic and foreign researches have been conducted on the skills and equipment of atmospheric pressure hot air drying. For example, domestic hot pepper dehydration through-flow drying experiments, research on hot air drying characteristics of carrot shreds, red dates, onions, and shiitake mushrooms, and foreign mathematical models of hot air convection dryers.
一系列 During the dehydration of fruits and vegetables, a series of quality changes may occur. These changes include chemical changes such as browning, lipid oxidation and discoloration; physical changes such as rehydration, cracking, arrangement and loss of aroma; changes in nutrients,
Such as loss of living and protein, microbial growth. In order to minimize the sensory changes of the vegetables during the boring process, the boring temperature should be reduced and the boring time should be shortened as much as possible. During this period, the microorganisms did not really die. In order to ensure the safety of the fruit and vegetables, it is necessary to Pre-heating: In order to prevent the entry of pathogenic bacteria, it is necessary to pay special attention to hygienic conditions when selecting and pre-processing various materials; in order to effectively control the quality of dehydrated pistils, it is necessary to study the quality parameters and response of dried products Kinetic data on chemical changes, vitamin destruction, enzyme inactivation and microbial lethal conditions.
2. Soaked and dehydrated
Infiltration and dehydration of fruits and vegetables refers to immersing a fruit or arugula in a solution with an infiltration pressure, that is, a sugar solution or a salt solution, at a certain temperature. The semi-permeability of the cell membrane is used to transfer the water in the material to the solution to remove part of the water A skill. Compared with the traditional hot air dehydration, because the water transfer surface does not change phase, that is, no heating is required, so the dehydration infiltration dehydration has the characteristics of low energy consumption and less loss of nutrients. Because it can remove the moisture from the fruit and agar in a short time without damaging its arrangement. So that they can still maintain the original flavor, color, nutrients and quality, and feel almost the same as when fresh. Therefore, it is a promising processing skills.
In production, soaking and dehydration can be used as a pretreatment method for fruit and vegetable processing, combined with methods such as boring, freezing, and storage of fruits and vegetables. When the fruits and vegetables are soaked and dehydrated, the drying time of the product can be shortened by 10% l5%. At the same time, because of the reduction in volume and weight, the boring payload is increased by 2-3 times. This greatly saves energy consumption.